Vests (not the attire) are 1 Millionth of Steem. They are what determines your rank in the sea, i.e.: Red Fish, Minnow, Dolphin, Orca, or Whale.
Vests are directly related to the amount of Steem Power in your account. If you Power Down, then you will lose Vests, because you are removing SP from your account. If you Power Up, you will gain more Vests. So you want to be layering on those Vests, the sea water can get pretty cold, so keep warm and gain SP.
How do you gain Vests? Through SP, so basically, by Commenting, Posting, Upvoting and Powering Up.
The question I had was: How many Vests do you Earn per 1 Steem Power. In other words, for every SP you gain, how many Vests will that grant you?
Assuming you are not Powering Down or Up, and you want to do some simple math to figure out how much you will get from your upcoming curation rewards, here's the formula:
- Take your current amount of Vests, which is now found under your Rank Icon on the Steemitboard website.
- Divide it by your current amount of Steem Power.
- You will get a approximate amount around, but a little higher than 2000.
So for me, it was 598 688 Vests, divided by 291.211 SP = 2055.856
So you can simply round things to around 2000 Vests per 1 SP. A Post that curates around 9 SP will generate 18 000+ Vests. A comment that curates 0.03 SP will grant you 60+ Vests.
Note that Vests are not tied to SBD, so the amount of SBD earned doesn't change the amount of Vests in your account.
This can be a good way to calculate, estimate, and predict, how quickly your Rank in the Sea will grow or when you should graduate from Red Fish to Minnow, and so forth.
I'll give credit to 
So layer on those Vests, and maybe the attire too seeing as Winter is approaching. Keep on Steeming folks!
(Both images are screenshots I took of the Steemitboard.com website, from my profile, and cropped them.
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