In recent years, the volatility of pension fund deficits has been dampened by pension fund assets behaving more similarly to pension fund liabilities. This is partly because bonds make up a bigger share of assets than a decade ago, and partly because bonds and equities are moving more closely than before. Both factors have increased the correlation of assets with pension funds’ liabilities which tend to be intrinsically bond-like. This matters because the volatility of pension deficits can affect pension fund investment decisions. Given their size, changes in pension fund asset allocation can materially affect asset prices.