tl;dr add tk when you hit a wall (abbreviated from 'to come', yet spelled with k as tc appears in many words)
I slice my latke with a pocketknife.
Ratios (count / total) and percentages:
PG: 0.00047%
TK: 0.00046%
KK: 0.00045%
HQ: 0.00042%
FN: 0.00042%
Every other one here I'd expect to see: Postgres, kk/okay (and my initials), headquarters, function. Of course there's Tcl/Tk but not used nearly as much as it could.