Is a low SD indicative of anything?

[SomethingClever]

As I continue to analyze every facet of my play at 2/4, I recently noticed that my SD is significantly lower than it was at .5/1 and 1/2.

I have a 22K sample size at .5/1 where my SD is about 17.5

In my 13K at 2/4, it's significantly lower, at just above 15.

Over the last 5K hands or so, it's much lower at just above 12. This has been the worst part of a bad stretch, and I'm wondering what, if anything, this low SD indicates.

Other relevant stats:

VPIP
.5/1: 16.5
2/4: 13.5

PFR
.5/1: 8
2/4: 7.8

AGG (TOT)
.5/1: 2.8ish
2/4: 2.4ish