pk1,pk2,sortable_with_nulls
a,a,
a,b,
a,c,
a,d,
a,h,
a,i,
a,j,
a,l,
a,n,
a,t,
a,u,
a,w,
a,z,
b,b,
b,c,
b,d,
b,g,
b,i,
b,l,
b,q,
b,t,
b,x,
b,z,
c,e,
c,i,
c,j,
c,n,
c,o,
c,s,
c,w,
c,x,
d,b,
d,d,
d,i,
d,m,
d,q,
d,r,
d,u,
d,v,
d,z,
e,c,
e,e,
e,f,
e,g,
e,h,
e,i,
e,m,
e,q,
e,t,
e,u,
f,a,
f,b,
f,c,
f,d,
f,f,
f,h,
f,o,
f,p,
f,r,
f,w,
g,b,
g,j,
g,k,
g,m,
g,s,
g,t,
g,y,
h,g,
h,i,
h,m,
h,r,
h,s,
c,r,0.0058960835839930725
b,v,0.024786361898188725
e,b,0.040231673144616176
f,k,0.045346811013382116
d,o,0.04551570098321833
g,d,0.051446079972376046
a,g,0.06955514882374092
g,h,0.06958542124833644
a,x,0.07099308600903254
b,s,0.07524386007376704
h,d,0.08150198744788395
e,a,0.0913268866309852
h,q,0.099083124393048
f,y,0.09917846167904198
g,z,0.10350187727039162
e,p,0.1262462698093887
f,e,0.13141180642048544
b,w,0.15919784298073125
g,g,0.1804160719608544
c,b,0.19007877450229604
e,k,0.19061037094792832
b,m,0.2131543122670404
c,p,0.21395287710598743
f,j,0.22136720007399002
d,k,0.24330516387675716
h,a,0.24774372359828423
d,w,0.26455462565889964
e,r,0.2650227795434089
f,t,0.26536750832497336