Red Robin Gourmet Burgers, Inc. ( RRGB - Free Report ) has plunged 66.1% year to date, compared with the industry 's decline of 10.2%. The dismal performance can be primarily attributed to inflationary pressures. A decline in margin continues to affect the company. During the quarter, the cost of sales rose 12.7% year over year to $70.6 million, while as a percentage of restaurant revenues, the metric increased 180 basis points to 25%. Other operating costs increased 2.7% year over year to $52.9 million. Red Robin has been strategically increasing prices to mitigate the impact of inflation while maintaining a strong value proposition at the same time.