Safe MPs

During a discussion over the pros and cons of AV and FPTP (and PR) someone made the comment that AV was pointless as "it won't affect most MPs, only about a 100 or so". I replied that I didn't think that sounded right.

But it doesn't matter if it doesn't sound right to me, it only matters what the data shows and as it so happens I have the 2010 election results. The statement posed was that the majority of MPs won't be affected by AV as they've already polled over 50% of the vote; the results below show which didn't:

Party	<50%	=50%	>50%
Speaker	1	0	0
Alliance	1	0	0
Conservative	180	0	126
DUP	8	0	0
Green	1	0	0
Independent	0	0	1
Labour	181	1	76
Liberal Democrat	46	0	11
Plaid Cymru	3	0	0
Scottish National Party	6	0	0
Sinn Fein	3	0	2
Social Democratic and Labour Party	3	0	0
	433	1	216

That's 433 out of a total 650 MPs whose winning position might be affected by AV.