Theresa May is in Davos today and she'd be forgiven for wanting to say there indefinitely. Today's opinion pages are full of critical articles and the Sun's Harry Cole reports that the number of letters calling for a confidence vote is perilously close to the 48 needed to trigger one.

For those in need of a refresh: to call a vote of no confidence in a Conservative leader, you need 15 per cent of the parliamentary party (48 MPs) to send a letter calling for one to the chair of the party's 1922 committee, Graham Brady. The number is said to have reached 40 and one backbencher tells the Sun that Brady is "ashen-faced" at the prospect of getting more.

Is it all over for Theresa May? There are a couple of things to remember whenever you read about imminent confidence votes. The first is that the really, really important numbers as far as the PM's position goes are 50 and 158. Why 50? Because that's Brady's age: he easily has another 20 years at the top of Conservative politics and isn't going to risk that, or abandon his traditional discretion, just to prolong the age of May.

But the still more important number is 159 - half the number of Conservative MPs plus one, i.e. what you need to actually pull off a vote of no confidence in May's leadership of the party. In this week's Spectator, James Forsyth details the mood in the parliamentary party well, which is that things are bad, but the time for change is not yet here.

Should the 48-mark be upon us, it's still highly possible that May would either be pressed upon to stay or would decide herself to fight the vote. Don't forget that both Margaret Thatcher (the first time) and John Major saw off confidence votes. Theresa May can do the same if she is feeling even mildly stubborn. And Theresa May manages that an awful lot of the time.