500sp gives you 5,7% of the bots vote value. remember sbd will go up & down as following the price of steem, il attach link. https://steemit.com/stax/@silvergoldbotty/updated-stax-upvotebot-and-curation-community-faq-page-with-tier-adjustments
So even if sbd moves , you will always get that % of the bots value. In my case i have 57%....