I used the API scrape all user's avatar_id.
Here's the ranking
1~12(Descending)
#12
post #1307323 number:21
#11
post #585543 number:22
#8
post #496216 number:23
post #426790 number:23
post #308647 number:23
#7
post #79554 number:24
#5
post #1214147 number:26
post #1506084 number:26
#4
post #546281 number:41
#3
post #626747 number:42
#2
post #1 number:55
#1
post #287182 number:75
13~(Ascending)
#13
post #1367432 number:19
post #366191 number:19
post #1094632 number:19
#16
post #421 number:17
post #21994 number:17
post #1358451 number:17
#19
post #701921 number:16
post #1526296 number:16
post #1503498 number:16
#22
post #423133 number:15
post #807155 number:15
#24
post #80442 number:14
#25
post #583854 number:13
post #1453931 number:13
post #479403 number:13
post #308372 number:13
post #903968 number:13
#30
post #728443 number:12
post #1305214 number:12
post #1526874 number:12
post #324900 number:12
post #1022036 number:12
post #539888 number:12
post #526525 number:12
post #282245 number:12
post #743873 number:12
post #124147 number:12
post #759717 number:12
post #609764 number:12
post #172263 number:12
post #186730 number:12
#45
post #735523 number:11
post #929177 number:11
post #925916 number:11
post #664515 number:11
post #1366984 number:11
post #1544455 number:11
post #1059998 number:11
post #166087 number:11
post #426556 number:11
post #258409 number:11
post #958984 number:11
post #316683 number:11
#2 is the bug, check below cases
#5 two posts are the same picture
If you want to know your avatar's count or more detail, check this sheet
Updated by KiraNoot