Two column data of baseline-corrected sensitivity-drift (in units of PPM) of a Commercial-Off-the-Shelf VC/OCXO with respect to time (in units of years). The dataset spans about 0.7 years. Two spreadsheets are included in the workbook. The spreadsheet titled "Raw Data w. gaps 'as-collected'" contains the raw drift data, without any gap-filling. This shows the aging of a VC/OCXO's baseline-corrected sensitivity to constant input voltage. Text entries of "gap" in these numeric data arrays denote breaks in the data collection process attributable to other demands on the facility. The spreadsheet titled "Gap-filled data set" is needed for performing Allan variance analysis. Gaps in the data were mitigated by employing the technique outlined in D. A. Howe, C. Champagne and N. Schlossberger, "A Total Imputation Algorithm that Fills Gaps in Time Series Measurements for ADEV and Phase Noise Characterizations of Power-law Noise Models," 2022 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS), Paris, France, 2022, pp. 1-2, doi: 10.1109/EFTF/IFCS54560.2022.9850921.