Hi Ivy! I'm currently working on a new slider, so that you can slide to what you desire to see... ^^

I will try to explain :)
The value that you currently see on SteemWorld is your real (potential) vote value. When you vote a post that didn't receive any votes yet, the shown vote amount will be much less (can be down to -50%), because based on the new reward curve the total payout of the post is too low to reach the point where the curve gets more linear, like it has been before the HF.

So, you are really voting 18 cents (in rshares), but not all of your potential vote amount will be paid out, if no other voters increase the total payout amount enough to reach the linear point. For example, when a big whale votes the same post later with a strong vote, a higher percentage of your potential rshares will be used for the payout and your 18 cents can really be reached.

I will soon add a slider, so that we can define the payout amount of the target post on SteemWorld. I hope this helps a bit to understand how it works ;)