Hello and welcome to more or less on the BBC World Service, where you're

weekly guide to the numbers all around us in the news and in life, and I'm Kate Lamble.

For the last few weeks, the news has been dominated by Afghanistan and the consequences of

the withdrawal of American troops. I fellow Americans, the war in Afghanistan is now over.

The last American military plane left from Kabul's airport at 3.29 pm Eastern time.

The eruption of celebrity gunfire by Taliban supporters in the city of Kabul.

And this big news came with some pretty hefty statistics. This was US President Joe Biden

addressing the nation. After more than $2 trillion spent in Afghanistan,

costs that researchers at Brown University estimated would be over $300 million a day for 20 years

in Afghanistan for two decades. The study from Brown University, which Joe Biden mentioned there,

actually suggests American operations in Afghanistan and Pakistan between 2001 and 2021,

cost $2.3 trillion. And several of you, including James Kelly and Helen Andre, emailed more or

less at BBC.co.uk to ask whether that could possibly be true. Helping us run the books is Todd

Harrison, a senior fellow at the Center for Strategic International Studies where he studies

the US Defense Budget. About one trillion of that is the military's cost of operations in

Afghanistan to date. So this one trillion, it isn't the US Defense Budget as a whole,

it just counts a particular fund which covers the additional cost of the war. So for example,

it does not include the portion of the salary that people would have been paid without Afghanistan.

All that's included in the war-related cost is the extra pay the service members received

because of deployments to Afghanistan. That's combat pay and other benefits. But that still leaves

another $1.3 trillion to help us make up this estimate for the total cost of the conflict.

About $60 billion of that was spent by the US State Department in Afghanistan paying things

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