Changes in levels of cash is a measure of liquidity. Liquidity refers to a measure of the ability of a debtor to pay its debts as they mature. Thus, with more money, they will be better able to pay its debts, and vice versa, with less money, they will be able to pay debts as they mature. Changes in levels is a measure of cash liquidity. Liquidity refers to a measure of the ability of debtors to pay its debts when due. So with more money, they will be better able to pay its debts, and vice versa with less money, they will be able to repay the debt as it matures.