Fusion-io (FIO), which develops data solutions, is sinking after William Blair analyst Jason Ader downgraded the stock to Market Perform from Outperform in a note to investors earlier today. The company is likely to report weaker than expected results in the second half of this year, as its bookings with corporate customers appear to be slower than expected, the analyst wrote. Demand for Fusion-io's server attached PCIe card, which are used for data storage, is weaker than expected, Ader explained. The analyst now expects the company's corporate sales to increase 53% in fiscal 2013, down from his previous estimate of a 66% jump. Macro economic pressures, a slower than expected ramp of Fusion's new products, and the emergence of new competing products have contributed to the slowdown in Fusion's sales, the analyst believes. In early trading, Fusion slumped $1.60, or 7.55%, to $19.60.