A declining gross profit ratio occurs when a company's gross profit decreases as a percentage of its sales revenue over time. The gross profit ratio is calculated by dividing gross profit by net sales and multiplying the result by 100. When this ratio falls, it indicates that the company is earning less gross profit from each dollar of sales than it did previously.

Several factors can cause a declining gross profit ratio. One common reason is an increase in the cost of goods sold (COGS), such as higher raw material, labour, or production costs. If a business cannot pass these increased costs on to customers through higher prices, its gross profit margin will shrink. Another cause may be increased competition, forcing the company to lower selling prices to maintain market share. Changes in product mix, inventory management issues, or excessive discounts can also contribute to a lower ratio.

A declining gross profit ratio is often viewed as a warning sign because it may indicate weakening operational efficiency or growing cost pressures. If the trend continues, it can reduce overall profitability and limit the company's ability to cover operating expenses, invest in growth, or generate returns for shareholders.

However, a temporary decline is not always negative. For example, a company may intentionally reduce prices to attract new customers, enter a new market, or increase sales volume. Therefore, analysts usually examine the reasons behind the decline and compare the ratio with industry averages and previous periods. Understanding a declining gross profit ratio helps managers and investors identify challenges and make informed business decisions.