Google has the answer to everything. Well actually not quite everything, it seems…
That’s because when I sat down to write this blog about the Queen and Prince Philip’s Platinum Wedding Anniversary in November this year, I thought it would be interesting to see how many couples actually celebrate 70 years of marriage.
The answer is Google doesn’t know.
And the more I dug around, the more I realised the reason why. It’s incredibly rare.
So if Google can’t tell us, let’s see if we can come up with an answer.
Fundamental to the problem is that there is simply no central record of how long marriages last until one of the couple passes away. But perhaps we can make some assumptions based on some of the statistics that the Office for National Statistics (ONS) do publish.
How likely are two people to both make it past their 90th Birthday?
In 1947 the median age for marriage was 23.7 for men and 20.5 for women[i], making Princess Elizabeth and Lieutenant Philip Mountbatten pretty typical of their generation, marrying aged 21 and 26. It also means it’s fair to work on the basis that for nearly any couple celebrating their Platinum Wedding Anniversary, they are both going to be in their nineties.
So the chances for making it past the age of 90 in England and Wales is 0.8%[ii]. That means that the chances of two people BOTH making it is:
0.008 x 0.008 = 0.000064
0.0064% chance of two people both making it past their 90th birthday.
How many people were married in 1947?
Fortunately, it is much easier to uncover how many people married in 1947. In fact 1947 is the very first year that the ONS not only holds data for the total number of marriages in England and Wales but also in which month they took place.[iii]
Certainly by choosing November, they were not following the trend. In fact with fewer than 30,000 marriages that month, it was the third least popular month for weddings that year.
Overall, the young princess and her naval officer beau were one of 401,210 couples to tie the knot that year. Statistics for Scotland and Northern Ireland appear more difficult to track down but it would be reasonable to extrapolate the numbers based on the overall UK population split, which suggests a figure for the whole of the UK.
466,000 UK marriages in 1947.
But what about divorces?
Data is not easily available for 1947 but it can be found for English and Welsh marriages in 1950[iv]. According to the ONS, 8.6% of marriages at that time ended in divorce, so we should discount them out from our 466,000 UK marriages.
466,000 x 91.4% = 426,000 non-divorce marriages in 1947.
How many Platinum Wedding Anniversaries might we expect this year?
So we have now have two critical pieces of data. The chances of two people making it past the age of 90 – the realistic milestone age to celebrate a Platinum Wedding Anniversary – and the number of marriages in 1947 that did not end in divorce.
Based on that we can multiply the two numbers together to give us a pretty reasonable estimate of the number of couples who will celebrate 70 years of marriage this year.
426,000 x 0.0064% = 27 Platinum Wedding Anniversaries
So, although there are no official statistics to back it up, it seems likely that only around 30 couples will join the Queen and Prince Philip in celebrating their Platinum Wedding Anniversary this year. Or to put it another way – just 60 people in the UK will mark 70 years of marriage in 2017 – that’s 1 in a million.
That’s why for me, forget the Jubilees; forget the birthdays. For the Queen and Prince Philip their Platinum Wedding Anniversary is the pinnacle of their long list of incredible milestones. And we, the British people, must join them in marking this historic moment.