Scratch benchmark. Benchmark Log has the average milliseconds, while Detail has milliseconds for each run. Put the block between START and END. START and END should take the name of the test as its first argument. END can take the least seconds it should take - for example, if you use "wait for 1 seconds" you put 1 there.
FYI The epoch time it uses is UNIX epoch - feel free to use that! (946684800000 + floor of (days since 2000 * 86400000))