The Conservative Party have secured a landslide victory in the UK General Election 2019, remaining committed to maintaining a spend of 2% of GDP on defence and promising to increase funding to the Armed Forces each year by 0.5% above inflation.
You may have heard talk of "2% of GDP", "the NATO target of 2%, "the NATO spending commitment" as parties campaigned ahead of the election, and if you read some of the election manifestos you will see a version of it again.
But what is '2%' defence spending?
It can sound like political and economic gobbledygook, but it is a relatively simple concept.
It s a commitment that the UK will spend 2% of its national income (also known as 'Gross Domestic Product' or GDP) on defence.
In other words, £2 out of every £100 spent in the UK will be spent on defence.
That means if the economy is growing defence spending will go up at least at the same rate; and if the economy is doing really well, growing faster than prices are rising, defence notionally has more spending power.
But if there is a recession, when the economy gets smaller, defence spending might also fall with it.
After the Cold War, European defence spending was falling, so in 2002 NATO members agreed a non-binding goal that they would each spend at least 2% of national income on defence.
The idea was to stop spending going any lower than it already was.
It didn’t really work - the UK was one of very few to remain at or above 2%.
At the 2014 Wales NATO summit, allies renewed their pledge to spend 2% on defence, by stopping cuts and increasing spending so that it would be back to 2% of national income by 2024.
When the renewed pledge was made some were predicting UK defence spending would fall below 2% of GDP that year, though in the end, it didn’t.
NATO has 29 member countries. According to NATO estimates, the UK is one of seven alliance members to meet or exceed the 2% spending target.
Has 2% been an election issue?
It's been a sort-of issue in the last two elections, but not one that has been a significant point of difference for the biggest parties.
At the 2015 General Election none of the main parties, apart from UKIP, would commit to keeping defence spending at or above the 2% goal.
However having won that election, David Cameron’s government then committed to meeting the target for at least the next five years.
When the 2017 election was called, the Conservatives, Labour, the Liberal Democrats, and UKIP all committed to keep meeting the 2% pledge in their manifestos.