I'm sure this is a dumb question but why are 6J tick values different?

[IronFist]

I just made a +2 tick trade and made $25.00. Then I made a -2 tick trade and lost $24.99.

The first one was long and the second one was short.

Do you get credited interest on short positions or something?

I'm sure there's an obvious reason for this...

 

[Pippi436]

P/L should always be $12.50 per tick, your penny certainly doesn't have anything to do with interest.