Time? Nope - the first block ever found on the pool was pretty slow coz the pool was tiny.
It was also lucky (less than 100%)
However, Diff% is what matters for rewards, and this one is 542% at the moment.
The 2 largest are there on the Web site Blocks page at the end of October - the largest being 928.788%
Now for that CDF related number
0.99557285335217 542.000% 1 in 225.9
i.e. we expect to average, over time, 1 in 225.9 blocks to be over 542%
Out of curiosity what is the actual number of blocks over 542% since the beginning of the pool? Including the block we're on now we have 4 out of the last 88 listed on the blocks page (or 1 in 22).