Looking at the criteria from the CTP balance page.
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The CTP token is staked and is the primary token for mail verifications. Every time you take part in a mail verification, you will earn a portion of the total rewards pool. Your active portion is based on the number of verifications you take part in versus the total verifications.

When you stake CTP on ListNerds you will earn a portion of the passive rewards pool. Your passive portion is based on the amount you have staked versus total staked across the site.
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I would guess that I am voting on more of the post that get verified each day.
I vote on around 5 per day which is how many votes I get per day with 600 CTP. Maybe I am lucky and vote on the ones getting verified. Are you voting each day?

!CTP
!PIZZA