Hello jtfish,
when you open your wallet you will see at the bottom: The estimated value is based on a 7 day average value of Steem in US Dollars.
In the last seven days the price of Steem and SBD gat great fluctuations. Just have a look at Poloniex for instance. As the price went up a bit the last days you will see your total value increasing again.
Hope this helps.