The FTSE 100 index reached a new closing high as the value of the pound declined against the US dollar. The index rose 1.62% on Monday, buoyed by the weak pound, which boosted the earnings of companies with significant overseas operations. However, the FTSE 100 remains below its all-time high of 8,047.06 and has lagged behind some European and US indices in terms of gains this year, facing challenges in attracting new listings.