This point is quite interesting and I've found some statistics for his feud with Cena from 2009.
In their feud this year, John Cena and Randy Orton had 23 live event matches, 2 dark matches and 5 matches on WWE TV. 30 matches in total. Out of those, John Cena won 28 and Randy Orton won 2. They also had 50 tag matches this year with 35 of those being on live events, 5 being dark matches, 10 on WWE TV and 2 where they were forced to team together.
Orton won 2 of 30? Talk about getting destroyed.