How are Curation Rewards calculated?

Hello,

after I have already done some interaction on this platform, the first Curation-Rewards have arrived on my account. Here is a small screenshot:

Now it strikes me directly that the curation percentage is very different, although I mostly used the same voting strength. Maybe there were some minor changes, but my rewards vary from 0.015 HIVEPOWER and 0.05 Hivepower, which is quite a difference. (0.015 one is not in the screenshot)

I am very interested in how this difference comes about. How is it decided which of my votes (in terms of my reward in terms of curation rewards) is worth more? Could someone provide me with a reference on this.

Best regards
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