DEFINITION of 'Defensive Interval Ratio'
An efficiency ratio that measures how many days a company can operate without having to access noncurrent (longterm) assets.
The defensive interval ratio (DIR) is calculated as:
DIR = Current Assets / Daily Operational Expenses
Also known as the "Defensive Interval Period".
INVESTOPEDIA EXPLAINS 'Defensive Interval Ratio'
The DIR is thought by many people to be a better liquidity measure than the quick and current ratios. Because these ratios compare assets to liabilities rather than comparing assets to expenses, the DIR and current/quick ratios would give quite different results if the company had alot of expenses, but no debt.
The DIR is not a replacement to the other ratios, but a complement. As with all financial analysis, a prudent investor will use a basket of different analysis when deciding on whether a company is a good investment.

Quick Ratio
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