If Cash Flow Margin increases over time:
An increasing Cash Flow Margin generally indicates the company is more able to convert its sales into cash.
If Cash Flow Margin decreases over time:
A decreasing Cash Flow Margin generally indicates the company is less able to convert its sales into cash.
If Cash Flow Margin stays the same over time:
An unchanged Cash Flow Margin generally indicates the ability of the company to convert its sales into cash has remained the same.