The long-term stratospheric carbon tetrafluoride (CF₄) increase has been determined from infrared high spectral resolution solar occultation Fourier transform spectrometer measurements between 3 and 50 hPa (∼20 to 40 km altitude) and latitudes from 50°N to 50°S during 1985, 1992, 1993, 1994, and 2004. The 1985 to 1994 measurements were recorded from the ATMOS (Atmospheric Trace MOlecule Spectroscopy) instrument at 0.01 cm⁻¹ resolution and in 2004 by the Atmospheric Chemistry Experiment (ACE) instrument at 0.02 cm⁻¹ resolution. Stratospheric volume mixing ratios, inferred from a polynomial fit to averages from the time periods considered here, increased from 49.37 ± 2.60 pptv (10⁻¹² per unit volume) in 1985 to 58.38 ± 4.14 pptv in 1992, 60.46 ± 2.97 pptv in 1993, 60.11 ± 3.60 pptv in 1994 and to 70.45 ± 3.40 pptv in 2004. The stratospheric CF₄ mixing ratio has continued to increase but at a slower rate than in previous years, for example, (1.14 ± 0.68)% yr⁻¹ in 2004 as compared to (2.77 ± 0.47)% yr⁻¹ in 1985, 1 sigma. Correlations of CF₄ with N₂O taking into account the increase of N₂O with time also show the increase in the stratospheric CF₄ burden over the two decade measurement time span. Our space-based measurements show that the slowdown in the rate of CF₄ accumulation previously reported from surface measurements through 1997 has propagated to the stratosphere and is continuing.