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Nope.

Although Activity Monitor does provide some basic numbers on transfer rate and I/O operations in the Disk Activity tab. It's not designed for benchmarking, though, since it only displays aggregate, not per-drive.

There are several tools you can download and run, for example SpeedTools Quickbench and DiskTester, though they're not free. I think Geekbench also does drive benchmarks.

You can always just time a file move/copy/duplicate to get a simple real-world benchmark, though that won't help if you need more detailed metrics.
 
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