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value of usd/steem ?

Is the value they show for an upvote USD or Steem Dollars?

Its in USD as shown in the screenshot.

SBD aka steem dollar, if value of steem dollar goes down your reward go down as well because its adjusting. But then again i could be wrong.
https://coinmarketcap.com/currencies/steem-dollars/

That should be as a result of fluctuation in the SBD.

I stand to be corrected. #OWB