Song: "Look What You've Done To My Heart"
Artist: Marilyn McCoo & Billy Davis, Jr.
Peak position on the Cashbox Singles chart: #61
Number of weeks on the Cashbox Singles chart: 8
Weekly data:
| Week ending | Rank | Title | Artist | Label |
|---|---|---|---|---|
| August 20, 1977 | 85 | Look What You've Done To My Heart | Marilyn McCoo & Billy Davis, Jr. | ABC 12298 |
| August 27, 1977 | 80 | Look What You've Done To My Heart | Marilyn McCoo & Billy Davis, Jr. | ABC 12298 |
| September 3, 1977 | 71 | Look What You've Done To My Heart | Marilyn McCoo & Billy Davis, Jr. | ABC 12298 |
| September 10, 1977 | 67 | Look What You've Done To My Heart | Marilyn McCoo & Billy Davis, Jr. | ABC 12298 |
| September 17, 1977 | 64 | Look What You've Done To My Heart | Marilyn McCoo & Billy Davis, Jr. | ABC 12298 |
| September 24, 1977 | 63 | Look What You've Done To My Heart | Marilyn McCoo & Billy Davis, Jr. | ABC 12298 |
| October 1, 1977 | 61 | Look What You've Done To My Heart | Marilyn McCoo & Billy Davis, Jr. | ABC 12298 |
| October 8, 1977 | 66 | Look What You've Done To My Heart | Marilyn McCoo & Billy Davis, Jr. | ABC 12298 |
Rankings greater than 100 are from the Cashbox 'Looking Ahead' charts.