If it feels as if Nigel Farage is rarely off Question Time, that's because he isn't. The UKIP leader is a "late addition" to tonight's panel in what will be his third appearance this year (the most recent was 25 April).

In fact, after tonight, Farage will have appeared more times on the programme than any other politician in the last four years. Phil Burton-Cartledge ranked the top five for the NS last year and here's an updated version:

Question Time appearances since 2009

1. Nigel Farage (14 after tonight)

2. Vince Cable (13)

3= Ken Clarke (12) Caroline Flint (12)

5= Peter Hain (8) Caroline Lucas (8) Theresa May (8) Shirley Williams (8)

It's easy to see why Farage appeals to producers. He's charismatic, inspires debate and helps them to fufil their requirement to give representation to smaller parties. But by any measure, 14 appearances is an overrepresentation.

I don't buy the argument that because UKIP has no MPs its representatives should be given no more airtime than those of the Greens or Respect. Broadcasters have to reflect public opinion as it is, not as it was in 2010 and UKIP has been outpolling the Lib Dems for months. And those liberals who campaign for electoral reform can hardly cite the distorted outcomes produced by first-past-the-post (UKIP polled 3 per cent at the last election and won no MPs, the Greens received 0.9 per cent and won one) as a reasonable guide for producers. But should the BBC's premier political programme have allowed the leader of a political party this much coverage? Undoubtedly not. If UKIP is to be fairly represented, give some of the B-team a chance (the party has 11 MEPs), rather than simply booking the star striker.

If David Cameron, Nick Clegg or Ed Miliband had appeared three times this year, their counterparts would be understandably furious. We shouldn't hold Farage to any other standard.