When was the last time we hammered a local rival ?

With the exception of Huddersfield Town ff , I can't remember the last time we recorded a big win in a local derby. You would , probably , have to go back to the 3-0 home win over Sheffield Wednesday in December 2001 . The biggest home win , that I can remember , over Rotherham United was also 3-0 , way back in the spring of 1982 (Alan Birch 2 and Colin Walker were the scorers , I think) . Surely , we're due a big win , if only by the laws of averages ?
The fact that I'm going on a family do to Rotherham tomorrow night could well be influencing my train of thought (!)