https://imgur.com/i18zNxf

A couple weeks ago I purchase $100 of BTC thru Coinbase. I transferred the money to Waves exchange. I think after fees I had about $96. With this $96 of BTC I traded for Starta(STA) at .45 per Sta..Later when Sta reached .84 I traded back to Btc. my BTC USD value showed I had a value of $47.50. If I bought at .45 and sold at .84 I would have thought my money would have almost doubled. Instead It got cut by 50%. Did I do something wrong or did waves or someone else?
I have attached a page from Coinbase and one of Waves transaction, hopefully you can read it and explain to me what happened

the first columns are coinbase

May 12
Sent bitcoin               .01138819BTC
to bitcoin address                   _$95.94

May 12
Bought Bitcoin            .o1138659
Using VISA debit                    +100.00

The next page is Waves

May 12

exchange Sell: Starta/BTC              -136.8 Starta
18:38                                            .00547473BTC

Exchanne Buy: Starta BTC              +16 Starta
16.49                                            .00159968BTC

Exchange Buy: STARTA/BTC            +18.2 Starta
16:47                                            -1.81999617

Exchang Buy: Starta/Btc                 +2Starta
16.46                                             -.19999958

Exchange Buy: Starta/Btc                +2.2 Starta
16:45                                             -.21999953

Exchange Buy: Starta/Btc                +98.4 Starta
16.43                                             .00983803








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