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Apple's 80% Charging Limit for iPhone: How Much Did It Help After a Year?
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Fully discharging is as bad or worse for battery longevity than fully charging. Battery tests on electric cars show dramatic improvements when kept in the 20-80% range. Can make the difference between <100K miles and >300K miles before the battery is toast.
Of course, it’s only $100 for a new iphone battery, so….
Of course, it’s only $100 for a new iphone battery, so….
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I still think that it would be fine to do a REAL SCIENTIFIC test - and it is a shame that apple does it not - or at least never ever published a transparently and seriously presented result!
There are more important factors that influence the lifetime and decline of a battery than many people think of.
My iPhone 14 Plus (purchased 13 months ago) has still 95% (apple battery app) or 96% (coconut battery app) .
I used most of the time normal charging, but do charge it during the day since about 6 months just if charging is possible by cable with the little old 10W charger.
When I go to bed or the capacity level is low, I use now always „optimized charging“.
From day one I protect my iP14 plus with the very good „SP“ - but this leads to really significant higher temperatures when surfing in the web or following YT etc when not at home. Even without any charging.
Charging - even without using it from lower capacity levels and still in the protection - leads also to significantly higher temperatures. Even much more if environmental temperatures are high.
So - if charging from a lower level I do this with „optimized charging“ AND I take the iPhone out of the protection at home or in the office. Make a test for yourself: you will be astonished, how much higher the temperature gets if you charge it in your cell phone cover!
The higher temperatures are in my opinion one of the most critical negative factors and largely underestimated!
Since charging from lower levels means always high inner temperatures, I try to avoid this by
a) preferring more, but „little“ charging amounts by charging my iPhone always already above 60 or 70%, if possible (in my car, at home, in office or hotel). Same for my iPadPro 11“ from 2021, although I use it at least 60% the time only on battery, not during charging by cable.
b) charging always in mode „optimized charging, since this is possible.
c) if at home or in the office always charging without the cell phone cover.
d) Even if you are obliged to charge from low capacities it is IMHO much better to do this in 2-3 portions with a pause that allows the iPhone/iPad to cool down - which needs not much time, if you take it out of the Cellphone cover while charging.
e) keep in mind that high inner temperatures in iPhones and ipads are also very bad for all the electronics inside!
So - avoiding unnecessary and critical temperatures will not only protect the battery itself but the as well thewhole electronics packed side-by side in the not-ventilated iPhone!
The screen is consuming always the most of the battery capacity. Not the CPU inside…
——-
1) The manufacturer -each of them claiming producing „according to apple standards“ - but shurely with NO significant enough quality controls. So - it begins even before a customers receives his own iPhone, iPad or Mac… this is the first step of the „lottery“.
I still use a MBP 15“ from 2011 (!!!) with its FIRST battery! capacity is still at 82%, after all these years. only since 2021 I began to use some other MBPs.
One of two further MBP 15“ models late 2015, one produced in 2017, has still 83% capacity, although used about 30% off charge, but I ever charge also „in between“ on the road regardless of the resting charge level. If used at home or in office, I always connect it with the cable-charger.
The other MBP model 2015 has been produced in 2015 and received a very good new battery in 2021 when battery capacity was (after 7years) at 81%. The new battery had 107% (!) capacity and even 103% after 2 years. now it has still 98%.
2) Temperature is very important. regardles if iPhone, iPad or macbook…
Not only the temperature of the environment, but especially the resulting temperature of the battery itself. FAST charging means always higher temperatures because of high current flux - especially when charging from very low battery level, which heats up exponentially more instead of less long charging.
Just my 2 cents..
BTW:
I chose the iPhone 14 PLUS because the Plus models have a much longer battery life in comparison to their power consumption.
There are more important factors that influence the lifetime and decline of a battery than many people think of.
My iPhone 14 Plus (purchased 13 months ago) has still 95% (apple battery app) or 96% (coconut battery app) .
I used most of the time normal charging, but do charge it during the day since about 6 months just if charging is possible by cable with the little old 10W charger.
When I go to bed or the capacity level is low, I use now always „optimized charging“.
From day one I protect my iP14 plus with the very good „SP“ - but this leads to really significant higher temperatures when surfing in the web or following YT etc when not at home. Even without any charging.
Charging - even without using it from lower capacity levels and still in the protection - leads also to significantly higher temperatures. Even much more if environmental temperatures are high.
So - if charging from a lower level I do this with „optimized charging“ AND I take the iPhone out of the protection at home or in the office. Make a test for yourself: you will be astonished, how much higher the temperature gets if you charge it in your cell phone cover!
The higher temperatures are in my opinion one of the most critical negative factors and largely underestimated!
Since charging from lower levels means always high inner temperatures, I try to avoid this by
a) preferring more, but „little“ charging amounts by charging my iPhone always already above 60 or 70%, if possible (in my car, at home, in office or hotel). Same for my iPadPro 11“ from 2021, although I use it at least 60% the time only on battery, not during charging by cable.
b) charging always in mode „optimized charging, since this is possible.
c) if at home or in the office always charging without the cell phone cover.
d) Even if you are obliged to charge from low capacities it is IMHO much better to do this in 2-3 portions with a pause that allows the iPhone/iPad to cool down - which needs not much time, if you take it out of the Cellphone cover while charging.
e) keep in mind that high inner temperatures in iPhones and ipads are also very bad for all the electronics inside!
So - avoiding unnecessary and critical temperatures will not only protect the battery itself but the as well thewhole electronics packed side-by side in the not-ventilated iPhone!
The screen is consuming always the most of the battery capacity. Not the CPU inside…
——-
1) The manufacturer -each of them claiming producing „according to apple standards“ - but shurely with NO significant enough quality controls. So - it begins even before a customers receives his own iPhone, iPad or Mac… this is the first step of the „lottery“.
I still use a MBP 15“ from 2011 (!!!) with its FIRST battery! capacity is still at 82%, after all these years. only since 2021 I began to use some other MBPs.
One of two further MBP 15“ models late 2015, one produced in 2017, has still 83% capacity, although used about 30% off charge, but I ever charge also „in between“ on the road regardless of the resting charge level. If used at home or in office, I always connect it with the cable-charger.
The other MBP model 2015 has been produced in 2015 and received a very good new battery in 2021 when battery capacity was (after 7years) at 81%. The new battery had 107% (!) capacity and even 103% after 2 years. now it has still 98%.
2) Temperature is very important. regardles if iPhone, iPad or macbook…
Not only the temperature of the environment, but especially the resulting temperature of the battery itself. FAST charging means always higher temperatures because of high current flux - especially when charging from very low battery level, which heats up exponentially more instead of less long charging.
Just my 2 cents..
BTW:
I chose the iPhone 14 PLUS because the Plus models have a much longer battery life in comparison to their power consumption.
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Forever? Most people get a new phone every couple of years, or can replace their battery at a pretty reasonable cost. It’s not worth that level of micromanaging, thinking every evening whether you’re going to need to the extra the next day.
I rather have full charge during the day and pay $100 something to replace it at an Apple store when I feel it has deteriorated enough. It takes them 1-2 hours.
You are right GreyOS: if you are changing your battery charging settings every day then you are overthinking it. That’s not what most people are saying though. If you don’t need the full battery capacity of the phone day to day, then you just leave the 80% limit on. However, on rare occasions when you might need more (say, because you are going on holiday) then switch to optimised charging to make use of the additional capacity that you have in reserve, the night before.
Personally, if I’ve had the 80% limit set every day that I’ve owned my phone. No micromanaging required, I just have the convenient opportunity to top up the battery during the day.
BTW: I’d disagree with your statement that most people swap out their phone every two years. That may have been the case a decade ago, when every year saw big step improvements in phone tech. Nowadays everyone I know keeps their phone for much longer. Why upgrade when your four year old phone still does everything that you need it to?
Isn't a battery level below 20% just as bad as above 80% ?
So if you limit charging to 80% but end up with a dead phone you've won nothing.
You should analyse how much battery you use up on most days, divide it by two and add it to 50%. Voilà, you've got your personal recommended charging limit. 😉
In addition to that the temperature can have a really high impact on battery longevity too. You could limit charging to 80% and do heavy load computing (e.g. videography, gaming) while connected to the charger and probably have a really bad battery health pretty soon.
Here's my data for the data lake:
iPhone: 15 Pro
First Use: 10 months ago
Cycle count: 308
Max. capacity: 93%
Charging behaviour: 100% cable, 99% of the time limited to 80%, charging every night
Typical use: A lot of battery draining background activities (e.g. GPS), regular heavy use (videography in hot climate, a lot of network traffic, occasional throttling because of overheating), i try to keep battery level above 20%
So if you limit charging to 80% but end up with a dead phone you've won nothing.
You should analyse how much battery you use up on most days, divide it by two and add it to 50%. Voilà, you've got your personal recommended charging limit. 😉
In addition to that the temperature can have a really high impact on battery longevity too. You could limit charging to 80% and do heavy load computing (e.g. videography, gaming) while connected to the charger and probably have a really bad battery health pretty soon.
Here's my data for the data lake:
iPhone: 15 Pro
First Use: 10 months ago
Cycle count: 308
Max. capacity: 93%
Charging behaviour: 100% cable, 99% of the time limited to 80%, charging every night
Typical use: A lot of battery draining background activities (e.g. GPS), regular heavy use (videography in hot climate, a lot of network traffic, occasional throttling because of overheating), i try to keep battery level above 20%
well,
owners of the „genius“ Titanium iP 15 have really bad luck:
The only way to transfer heat from the completely closed inner side to the environment ist to have a material that easily gets warm and so transfers the heat to the outside…
There is a chemical heat quotient for all materials. The aluminium material used still for the iPhone 14 has DOUBLE the capacity to transfer heat than the Titanium used for the iPhone 15 models (at least the „Pro“ models).
So it is not a miracle at all that Titanium bodies of electronic devices get much hotter than the ones with „classic“ aluminium…
So this is the most important reason why the iPhone 15 had and will have a heating problem that is VERY important and cannot be REALLY solved !
When apple claimed that they solved the problem by a new firmware, they are just lying: The only way to get rid of overheating WITHOUT decreasing the performance is changing the material of the outer surface. OR: decrease the demand of energy.
So IMHO they just throttelt down just the performance - which by far most of the customers will never realize because the performance of the iPhone 13, 14 and 15 is much more you ever need.
It is really shocking that one of the richest high-Tech Enterprise of the world pays engineers that are too dump to look at the since 100 years existing list of heat quotient (=heat transfer) that you find in every basic book about metals….
😊🤣🙄🫣
shame on you, apple!
it is the same kind of childish foolishness as with „antenna-gate“ for the iPhone when Steve jobs told us that we were just „holding it wring“…
As for me, I had instantly a look at that list when I heard about Titanium as the „revolutionary“ new material…. 🤣😂
and I was warned already before this buggy thing was hitting the market…
Not only the surface , but Also the thickness of the metal is important for the transfer of heat… mostly very high performance which produces a maximum of heat does not last long.
So - having some thicker metal around will instantly absorb a lot of the inner heat and transfer more tonte outside - so cool down the electronics inside. This effect of thicker material helps at least very good when the max. Performance lasts not long and even when this lasts long…
There is a reason why cooling devices for CPU (for example) have thick material with high heat quotient and a maximum of surface… which is just the opposite of the iPhone 15…
- The thinner the material the less potential for „absorbtion“ and transfer of the inner heat production
- The more of metal surface the better the transfer of heat.
- The better the heat quotient the better the transfer rate.
.
owners of the „genius“ Titanium iP 15 have really bad luck:
The only way to transfer heat from the completely closed inner side to the environment ist to have a material that easily gets warm and so transfers the heat to the outside…
There is a chemical heat quotient for all materials. The aluminium material used still for the iPhone 14 has DOUBLE the capacity to transfer heat than the Titanium used for the iPhone 15 models (at least the „Pro“ models).
So it is not a miracle at all that Titanium bodies of electronic devices get much hotter than the ones with „classic“ aluminium…
So this is the most important reason why the iPhone 15 had and will have a heating problem that is VERY important and cannot be REALLY solved !
When apple claimed that they solved the problem by a new firmware, they are just lying: The only way to get rid of overheating WITHOUT decreasing the performance is changing the material of the outer surface. OR: decrease the demand of energy.
So IMHO they just throttelt down just the performance - which by far most of the customers will never realize because the performance of the iPhone 13, 14 and 15 is much more you ever need.
It is really shocking that one of the richest high-Tech Enterprise of the world pays engineers that are too dump to look at the since 100 years existing list of heat quotient (=heat transfer) that you find in every basic book about metals….
😊🤣🙄🫣
shame on you, apple!
it is the same kind of childish foolishness as with „antenna-gate“ for the iPhone when Steve jobs told us that we were just „holding it wring“…
As for me, I had instantly a look at that list when I heard about Titanium as the „revolutionary“ new material…. 🤣😂
and I was warned already before this buggy thing was hitting the market…
Not only the surface , but Also the thickness of the metal is important for the transfer of heat… mostly very high performance which produces a maximum of heat does not last long.
So - having some thicker metal around will instantly absorb a lot of the inner heat and transfer more tonte outside - so cool down the electronics inside. This effect of thicker material helps at least very good when the max. Performance lasts not long and even when this lasts long…
There is a reason why cooling devices for CPU (for example) have thick material with high heat quotient and a maximum of surface… which is just the opposite of the iPhone 15…
- The thinner the material the less potential for „absorbtion“ and transfer of the inner heat production
- The more of metal surface the better the transfer of heat.
- The better the heat quotient the better the transfer rate.
.
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Good battery research paper posted above debunking the 20% myth, that got me using <9% way more than >90%, and I’m at 86% health after 5yrs.
Heat, and other mention # of cycles, as major battery stress factors, but if you believe the credible/corroborating batt research they become immaterial at lower SoC.
Thought I would add my data point to the hundreds already posted -- iPhone 13 Pro Max, almost 3 years old, and absolutely zero effort to maintain my battery health is at 83%. I fully charge overnight (the past year via MagSafe charger on my nightstand), but on average, the phone is around 40% (usually a little higher) at the end of the day and rarely ever got below 20%.
So the author babied his iPhone's charging for a whole year and even suffered without a phone due to not having a full charge to start the day and was at 94% after a year. 6% a year times 3 years of babying, is 82% projected battery health in 3 years. That's where I'm at without caring.
So the author babied his iPhone's charging for a whole year and even suffered without a phone due to not having a full charge to start the day and was at 94% after a year. 6% a year times 3 years of babying, is 82% projected battery health in 3 years. That's where I'm at without caring.
Seems almost impossible to still have 100% battery health after a full year. Based on your 1st year, will the 2nd year still be 100%? 3rd year still 100%? I mean, if a year and 265 charge cycles doesn't drop your battery health,, what will? And why is yours so different that everyone else?
As per rules of this forum, when someone asks for a source for information provided in a post the poster must provide a source or proof that the information is factual. I would like your source for your claim that Apple reduced cpu performance to mitigate heat in the 15 Pro/ Pro Max line and that they lied about it by saying it needed a software fix.. A source can't just be your opinion..
Debate rules for forum:
Sources. If you claim that something's a fact, back it up with a source. When evidence of your claim is requested, you can either provide evidence or retract your claim. If you can't produce evidence when someone asks you to cite your sources, we may remove your posts. If you started the thread, then we may remove or close the thread
Just to make sure the context of your numbers is clear, your cycle count is ~ 1000?
Thank you for the link ! 👍
but temperature of satellite environment is quite different from environmental temperatures on earth…
nevertheless using your link (thanks again!) I found this more elaborated or at least more real-life orientated which is based on loss of capacity per calibrated work units… really an article with a lot of interesting results.
For me the list at the end is the best answer for our question.
An other scientific result is that charging more than 90-92% will degrade battery-lifetime more, which should show that the 80% limit is too low.
The best result is charging between 50-75% high means that you will charge multiple times per day… unrealistic to follow this „ideal“ .
So - my take-away is to not discharge to less than 40% and end charging at about 90%.
This seems a realistic plan.
If one does this you will be in the mid of the results after nevertheless three (!) full years and still at round about 85%
This is exactly the result I had with 4 generations of cell-phones since I always use them for about 3 years.
So - my daily practise is not the best, but a perfect compromise of all different charging-regimes tested.
It must be said that now the price for a battery-replacement in Europe is down to about 90€ (much easier to change) for the normal and for the plus-models and about 120-130€ (more difficult to change) for the Pro and pro-max versions.
Therefore battery replacement is much cheaper than before and I am fine with a charging-regime that is not too complicated and/or often necessary.
Thanks again for the helpful links of scientific research.
.
One of the challenges of this thread is that we're treating Apple's Battery Health numbers like measurements from a scientific grade thermometer. In practice it's highly non-linear and not consistently calibrated.
In my experience 80% Battery Life ~ 0% useful. The last time I let the battery in my phone get down there, it would sometimes turn off as soon as I removed it from the charger. Even when it didn't I would get maybe a few hours of standby and a fraction of that in useful life. With a new battery, same phone/usage could go 50 hours between charges (100%->0% which is of course suboptimal for longetivity but I did anyway once or twice).
Others have also reported Battery Health going up slightly after going down. In practice your 100% and someone else's 100% may not be the same number of electrons. Similarly deterioriation curves may be slightly different. Today's batteries while amazing by historical standards are still mass-produced parts based on complicated chemistries with significant manufacturing variability.
The previous poster's battery may have been effectively ">100%" battery health to start and so still reports 100% battery health. I am sure it undergoes some wear with each charge cycle but it is just not yet visible through Battery Health.
It's not even that battery life varies from battery to battery but battery health depends on use and abuse. Batteries that are in phones left on dashboards in hot climates will suffer more. Watching "youtube videos" in bright sunlight on 5G is more detrimental than watching videos inside in a cool environment etc.
None of these phones have any inherent residual value to treat them like a fine work of art. It's less stressful to use the phones as you want than worry what will be the battery life in 5 years.
I agree doesn't make sense to stress over the battery but I think a lot of people don't like to waste things even if they are "consumables". I turn my lights off when I am not using them even though LED lights use a trickle of energy compared to previous and last for years (though like iPhone batteries some of mine are tedious to change). To use a car analogy, the first question is an iPhone battery like an air filter where yes it will vary but in the end you just change it (at least I never thought about it)? Or is it more like tires where we try to keep it properly inflated and use appropriate to the conditions?
For someone traveling by car to multiple client sites each day and keeps their phone on a magsafe charger while they drive, if going from 80%->70%->80% meant a much longer battery longevity than 100%->90%->100% that would seem an easy win as the 80% charge cap for that person would have 0 impact on their day-to-day life but could mean fewer battery replacements (which are at best a hassle).
On the other hand, for someone who goes through 80% of their battery per day, an 80% battery cap might be the worst choice. If 80% -> 0% -> 80% is worse than 100% -> 20% -> 100% they'd actually be wearing their battery out faster plus suffering the pain of Low Power and/or sudden shutdowns.
Or if we had actual credible data that best case and worst case usage habits only change battery longetivity by +/-10% we could all feel fine treating them like car air filters.
I agree for the most part that I try to minimize my use of consumables. Turning a led light off is no brainer. Decades of “training” and the light switch is flipped. However energy generation is not a consumable. With other “real” consumables, it’s not that obvious. If the mental energy to manage is more than the worth of the consumable I let it go. That’s not to say I waste consumables indiscriminately.
But hard personal data is impossible to project. And battery degradation is a complex interaction between age and cycles.
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Hi have 240 charge cycle but still 100% and from starting i am charging it to 80%
With the iPhone 15 models that came out last year, Apple added an opt-in battery setting that limits maximum charge to 80 percent. The idea is that never charging the iPhone above 80 percent will increase battery longevity, so I kept my iPhone at that 80 percent limit from September 2023 to now, with no cheating.
My iPhone 15 Pro Max battery level is currently at 94 percent with 299 cycles. For a lot of 2024, my battery level stayed above 97 percent, but it started dropping more rapidly over the last couple of months.
I left my iPhone at that 80 percent limit and at no point turned the setting off or tweaked it. There were some days when I ran out of battery because I was without a charger for most of the day, and there were other times that I had to bring a battery along to make sure I didn't run out of power. It wasn't always convenient to keep it at 80 percent, but there were days when it didn't have too much of an impact.
It was always a treat when the iPhone randomly decided to charge to 100 percent, which is something Apple has baked in to the 80 percent limit to ensure the battery level stays calibrated.
For the most part, I charged using USB-C rather than MagSafe, but there was some MagSafe charging mixed in. There was probably a 70/30 split between wired charging and MagSafe charging. I did often let my battery get quite low before charging, and it didn't sit on the charger for long periods of time too often. Most charging was done in a room at 72 degrees. I'm adding this context because temperature is a factor that can affect battery longevity, and wireless charging is warmer than wired charging.
You can compare your level battery to mine, but here are a couple other metrics from MacRumors staff that also have an iPhone 15 Pro Max and did not have the battery level limited.
I don't have a lot of data points for comparison, but it does seem that limiting the charge to 80 percent kept my maximum battery capacity higher than what my co-workers are seeing, but there isn't a major difference. I have four percent more battery at 28 more cycles, and I'm not sure suffering through an 80 percent battery limit for 12 months was ultimately worth it.
- Current capacity: 87%. Cycles: 329
- Current capacity: 90%. Cycles: 271
It's possible that the real gains from an 80 percent limit will come in two or three years rather than a single year, and I'll keep it limited to 80 percent to see the longer term impact.
I did set my iPhone 16 Pro Max to an 80 percent limit, but I don't know if I want to continue the test given the lackluster results I had from 2023 to 2024. Will the thermal changes in the iPhone 16 models make any difference? Maybe, maybe not. There's a 90 percent charge limit option too, and that might be more feasible than 80 percent for most people, especially those that have phones with smaller batteries.
Let me know your current battery capacity and cycle count in the comments below, and weigh in on whether you think Apple's limits are worthwhile.
Article Link: Apple's 80% Charging Limit for iPhone: How Much Did It Help After a Year?
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I don’t ever use the 80% limit and I’m at 94% health on 385 cycles on a launch day 15PM. I say turn it off and enjoy the nice large battery, not 80% of it.
I also charge off a 20W and standard USB-C cable all the time and I plug into my truck stereo (3A) for 25,000 miles a year.
Clearly, playing games on a phone - kills it’s battery, while watching Youtube - restores it.
I wonder if it is a Youtube Premium subscription that is responsible for this magic.
☺️
Thank you for the link !
but temperature of satellite environment is quite different from environmental temperatures on earth…
nevertheless using your link (thanks again!) I found this more elaborated or at least more real-life orientated which is based on loss of capacity per calibrated work units… really an article with a lot of interesting results.
For me the list at the end is the best answer for our question.
An other scientific result is that charging more than 90-92% will degrade battery-lifetime more, which should show that the 80% limit is too low.
The best result is charging between 50-75% high means that you will charge multiple times per day… unrealistic to follow this „ideal“ .
So - my take-away is to not discharge to less than 40% and end charging at about 90%.
This seems a realistic plan.
If one does this you will be in the mid of the results after nevertheless three (!) full years and still at round about 85%
This is exactly the result I had with 4 generations of cell-phones since I always use them for about 3 years.
So - my daily practise is not the best, but a perfect compromise of all different charging-regimes tested.
It must be said that now the price for a battery-replacement in Europe is down to about 90€ (much easier to change) for the normal and for the plus-models and about 120-130€ (more difficult to change) for the Pro and pro-max versions.
Therefore battery replacement is much cheaper than before and I am fine with a charging-regime that is not too complicated and/or often necessary.
Thanks again for the helpful links of scientific research.
.
Glad you found the links useful, but you lost me on deriving a 40-90 charge cycle as ideal (putting aside reserve power comfort levels). The MDPI paper (from my first post), figure 8, models a 0-50 cycling routine to last twice as long as 40-90 (both 50% bands) - and all three batt research sources seem to corroborate each other (to me anyways)…. that the lower SoC range you can conveniently use, the better.
Re: satellite temp differences - li-ions have a rather narrow ideal operating range… like that found on earth.
Re: upgrade cycle - with 3yr phone/battery upgrade cycles, imho, it may not be worth battery mgt at all - ime, the results of batt mgt really only start showing after 2-3 yrs. I keep my phones twice as long as you, and anticipate having your health #s after 6yrs (consistent with fig8 modeling above).