Marathon marathon history

After running my 11th marathon this year I asked our club statto to remind me of my other performances...

13/04/08 33 London Marathon 04:43:46
22/04/07 32 London Marathon 05:28:46
18/03/07 31 Rome Marathon 04:55:05
09/04/06 31 Paris Marathon 04:29:13
10/04/05 30 Paris Marathon 04:11:16
18/04/04 29 London Marathon 04:36:45
04/04/04 29 Zurich Marthon 04:23:00
06/04/03 28 Paris Marathon 04:12:00
14/04/02 27 London Marathon 04:29:51
30/09/01 26 Berlin Marathon 04:51:24
22/04/01 26 London Marathon 04:41:52

certainly quite a range of times...wonder if I could ever do sub 4?