For the first time since 1996 there was no Premier League side in the draw for the last eight.
"You can't put us all in the one basket in terms of deterioration," Ferguson said.
"Our performance against Real Madrid was outstanding and we should have been in the last eight. Unfortunately it wasn't to be."
The Scot did, however, concede that the period of regular English success in Europe now appears to be over.
"It is a little bit cyclical," he said. "Going back a few years, English teams were in the semi-finals and finals quite regularly.
"At the moment German teams are progressing, with the performance of Dortmund.
"Bayern Munich have also improved this year and Spain has been like that for a few years now."