Biggest UK (not)parkrun totals:
Witney 724 (not)parkruns
Nonsuch 578 (not)parkruns
Chelmsford Central 465 (not)parkruns
Maidstone 411 (not)parkruns
Riverside 342 (not)parkruns
Bushy Park 278 (not)parkruns
Brundall 197 (not)parkruns
Blackpool 186 (not)parkruns
Luton Wardown 186 (not)parkruns
Hull 182 (not)parkruns

Highest adjusted* average (not)parkruns per parkrunner: Witney with 281 parkrunners recording 724 (not)parkruns
Lowest adjusted* average (not)parkruns per parkrunner: Chelmsford juniors with 20 parkrunners recording 20 (not)parkruns
(* = adjusted according a statistical formula to take account of parkruns with very low numbers)

Additional stats for (arbitrarily chosen) Outeniquasbosch parkrun
12 parkrunners each completed 1 (not)parkrun, for a total of 12 (not)parkruns,
10 parkrunners each completed 2 (not)parkruns, for a total of 20 (not)parkruns,
11 parkrunners each completed 3 (not)parkruns, for a total of 33 (not)parkruns,
6 parkrunners each completed 4 (not)parkruns, for a total of 24 (not)parkruns,
2 parkrunners each completed 5 (not)parkruns, for a total of 10 (not)parkruns,
3 parkrunners each completed 6 (not)parkruns, for a total of 18 (not)parkruns,
5 parkrunners each completed 7 (not)parkruns, for a total of 35 (not)parkruns,
In total, 49 parkrunners completed 152 (not)parkruns

Worldwide 18815 parkrunners recorded 30592 (not)parkruns, with an average time of 34:20
In the UK 12621 parkrunners recorded 19787 (not)parkruns, with an average time of 32:43
In South Africa 2075 parkrunners recorded 3755 (not)parkruns, with an average time of 41:29
In Australia 1692 parkrunners recorded 2734 (not)parkruns, with an average time of 36:14
In Ireland 1445 parkrunners recorded 2487 (not)parkruns, with an average time of 34:55
In Germany 156 parkrunners recorded 371 (not)parkruns, with an average time of 34:40
In the US 186 parkrunners recorded 339 (not)parkruns, with an average time of 34:26
In Poland 145 parkrunners recorded 280 (not)parkruns, with an average time of 33:06
In Canada 151 parkrunners recorded 238 (not)parkruns, with an average time of 32:12
In Russia 97 parkrunners recorded 167 (not)parkruns, with an average time of 29:50
In Sweden 47 parkrunners recorded 86 (not)parkruns, with an average time of 33:14
In Denmark 42 parkrunners recorded 54 (not)parkruns, with an average time of 29:58
In the Netherlands 28 parkrunners recorded 51 (not)parkruns, with an average time of 32:00
In New Zealand 18 parkrunners recorded 51 (not)parkruns, with an average time of 44:46
In Italy 34 parkrunners recorded 47 (not)parkruns, with an average time of 28:49
In Malaysia 18 parkrunners recorded 43 (not)parkruns, with an average time of 41:27
In Norway 20 parkrunners recorded 33 (not)parkruns, with an average time of 29:12
In Finland 11 parkrunners recorded 23 (not)parkruns, with an average time of 44:26
In France 13 parkrunners recorded 22 (not)parkruns, with an average time of 33:08
In Japan 11 parkrunners recorded 17 (not)parkruns, with an average time of 33:57
In Singapore 5 parkrunners recorded 7 (not)parkruns, with an average time of 39:17