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This is completely natural/normal.
When the price of Steem moves up, the value of our upvote also moves up with it, and if the price of Steem moves down, the value of our upvote moves down with it.
There were some times in the past, when I could give around $0.10 upvotes.
All because of the relatively high Steem price, which was around $6 USD and $8 USD.
Nowadays the price of Steem is below $0.50 USD, and my upvote is worth around $0.01.
But this is still better than a few weeks ago and in the previous months.
People had to have 600+ Steem Power to cast $0.01 upvotes and so on.
Now, as you can see, 230 Steem Power is enough for a $0.01 upvote.

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