On that OBR Forecasting

As of yesterday, the OBR's expected deficit (or Public Sector Net Borrowing) for the year ending April 2015 was £90bn: see OBR table 1.3.

Here's a chronology of some earlier forecasts.

22 June 2010: George Osborne delivers his Budget forecasting a deficit for 2014-15 of £17bn (table C.6). He fell short by £73bn. 12 October 2010: George Osborne confirms his aim of eliminating the deficit by 2015. He fell short by £90bn. 23 March 2011: George Osborne delivers his Budget forecasting a deficit for 2014-15 of £46bn (table C.8). He fell short by £44bn. 29 November 2011: George Osborne delivers his Autumn Statement forecasting a deficit for 2014-15 of £57bn (table C.7). He fell short by£33bn. 21 March 2012: George Osborne delivers his Budget forecasting a deficit for 2014-15 of £52bn (table D.6). He fell short by £38bn. 29 November 2012: George Osborne delivers his Autumn Statement forecasting a deficit for 2014-15 of £62bn (table B.6). He fell short by £28bn. 20 March 2013: George Osborne delivers his Budget forecasting a deficit for 2014-15 of £71bn (table B.6). He fell short by £19bn. 5 December 2013: George Osborne delivers his Autumn Statement forecasting a deficit for 2014-15 of £84bn (table B.6). He fell short by £6bn. 20 March 2014: George Osborne delivers his Budget forecasting a deficit for 2014-15 of £95bn (table D.5). He overshot by £5bn. 3 December 2014: George Osborne delivers his Autumn Statement forecasting a deficit for 2014-15 of £91bn (table B.5). He overshot by £1bn. 18 March 2015: George Osborne delivers his Budget forecasting a deficit for 2014-15 of £90bn (table C.5). He gets it right. 8 July 2015: George Osborne delivers his Budget forecasting a deficit for 2014-15 of £89bn (table 1.2). He falls short by £1bn.

The purpose of this exercise is not to be rude about George Osborne's - or the Office for Budget Responsibility's - forecasting skills.

Forecasting is a tricky business. However well run, and independent, the OBR is.

So why does any of this matter?

Well, as is now well understood, yesterday the Chancellor got a £33.8bn windfall, mostly from modelling changes but also some modestly improved forecasts of receipts (see Table 4.8).

And that's a £33.8bn change in OBR forecasts since July.

And he's already spent two-thirds of it, according to the Resolution Foundation.

Spending it is bold, given the OBR's forecasting record. You have to really want to believe - really want to - that all of those earlier forecasting errors were anomalous. And that now, at last, the OBR's going to get it right.

I'm not saying Osborne was wrong to slow the pace of spending cuts (as those on the left put it) or spend more (as those on the right do). I'd be ejected from the Labour Party if I said that.

It's more that all of this bouncing around from Osborne feels a touch... unstrategic. An opportunistic, rather than a long term, economic plan?