We compare year-by-year:
- 1987-88 deficit $\approx 4$B, 1988-89 deficit $\approx 6$B → increases
- 1988-89 deficit $\approx 6$B, 1989-90 deficit $\approx 6$B → almost same
- 1989-90 deficit $\approx 6$B, 1990-91 deficit $\approx 8$B → increases
- 1990-91 deficit $\approx 8$B, 1991-92 deficit $\approx 6$B → decreases
- 1991-92 deficit $\approx 6$B, 1992-93 deficit $\approx 7$B → increases
- 1992-93 deficit $\approx 7$B, 1993-94 deficit $\approx 5$B → decreases
- 1993-94 deficit $\approx 5$B, 1994-95 deficit $\approx 6$B → increases
Count of years with increase = 3 years.