An article published in Nature claims that glaciers are losing 31% more ice and snow per year than 15 years ago according to 3D satellite measurements of all the world's glaciers with half the loss coming from North America.
Researchers have calculated that the planet's 220,000 mountain glaciers (that is, glaciers not connected to ice sheets) are losing 298 billion tonnes of ice and snow per year since 2015. I don't know what that is in terms of Olympic swimming pools but it would sink Switzerland under 7 meters of water. The melt has increased by 71 billion tonnes compared to the period 2000-2004. Melt rates in Alaska are some of the highest on the planet. The Columbia glacier is retreating 35 meters per year. Even the once stable Tibetan glaciers are melting. Only a few glaciers in Iceland and Scandinavia are growing, due to increased precipitation.
Researchers say that the melt will disrupt water supplies and increase sea depths. Glaciers are responsible for 21% of sea level rise, more than from ice sheets.