A record was developed, and subsequently there was a two-year lag in the actual decision. During this time, T-Bills fell 4.09 points. The Commission then reduced the equity rate of return by the same amount and later in response to Union’s arguments for a rehearing modified the T-Bill rate from 7.33 to 7.77 and reduced the adjustment to 3.65 points. The Commission then approved a rate that was substantially different from what was initially found. Union contends that the use of the T-bill data violated 556(e) and Due Process.