Keeping an eye on liquidity is important, not least for small businesses. It is relatively easily done with exel. But it is also useful to simulate different outcomes and see how things turn out liquidity. A simulation program you build easily in exel but there are also ready calculators.
Here is an example of Bplans.com. Click the launch button and you get a simulation directly in a graph.
Bplans writes: Many startups and small businesses fail despite being nominally profitable. When it is time to pay the bills, cash is king. Use this handy calculator to see the effect of sales, inventory, credit terms, and other variables on your company’s cash flow.