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Having delegated Steem power directly influences your Steem power during the time of delegation, which in return increases your accounts Voting value, which then gives higher rewards.

You can calculate your accounts Voting value on https://steemnow.com/upvotecalc.html
or you sign into your account from @busy website https://busy.org which has a better interface and you'll be able to get more details about your account.

I'm actually replying from https://busy.org.

Hope this helps.

Thanks.