This week on the BBC's More or Less program, Tim Halford is back with nearly half an hour's worth of numbering goodness.

And in this download edition, we're going to try something a bit different.

We're going to start with brand new items on whether it's possible to count how many birds die flying into windows

and the numbers behind Mozart's The Magic Flute.

Before moving on to cover the Reinhardt Rogoff spreadsheet mistake,

and Mrs. Thatcher by Numbers in new, longer versions.

Hello and welcome to a brand new series of More or Less, the program which serves up more numbers

than a catering tin of Number Etty Spaghetti. This week, we bring you a statistical verdict

on the premiership of Margaret Thatcher. We look at the mathematics of Mozart and we raise a

quizzical eyebrow at David Mitchell's BBC Radio 4 Quiz Show, the unbelievable truth.

In America each day, over two million birds die crashing into windowpains.

But first, spring has finally sprung. Oh no!

There I was in my kitchen with the family, listening to the Radio 4 Quiz, the unbelievable truth.

As you may know, the aim of the game is to deliver a hilarious monologue on a given topic,

almost all of which is false, and to smuggle five implausible truths

cunningly concealed amidst the lies, and one of the unbelievable truths which made it past the

panellists was this. In America each day, over two million birds die crashing into windowpains.

And at the end of that round, Mark, you've managed to smuggle three truths

past the rest of the panel. The second truth is that in America each day, over two million

birds die crashing into windowpains. But I just found this unbelievable.

Charlotte McDonald, I said, this is one for a statistical sleuth like you.

And well, the story starts in 1990. That year we were all dancing about to this kind of thing.

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