NRSVueS Isaiah 53:8, "perversion" not keyed/tagged for עֹצֶר

In the NRSVue, the first part of Isaiah 53:8 reads:

“By a perversion of justice…” the word “perversion” does not have a related key number, despite the fact that it clearly is translating  עֹצֶר.

Compare Isaiah 53:8 in the NRSVS, which reads precisely the same, and “perversion” is tagged.  

I run across this kind of thing pretty regularly with the NRSVueS, which is quite disappointing.