(IDEX Online) - Online searches for engagement rings have spiked ahead of Leap Day today - when women traditionally switch roles to pop the question.It's already a busy month for diamond sales because of Valentine's Day, but 29 February increases demand every four years, says eBay UK.The e-commerce giant says there's been a 220 per cent increase in searches for engagement rings compared to non-leap years."It's clear that February is one of our most exciting months, there's lots of proposals with Valentine's Day and with 2024's Leap Year," said Alice Marsden, head of luxury at eBay UK.Six out of 10 consumers prefer to shop for an engagement ring online, to keep the proposal a secret, she said.And so-called "placeholder engagement rings" are becoming increasingly popular. Six out of 10 couples say they'd consider buying a new engagement ring in the future, when the have a bigger budget.