the graph shows the number of passports issued by the Passport Office in the last 6 years. In how many years was the number of passports issued more than those issued in the previous year?

Let's compare the number of passports issued in each year with its immediate previous year:
* Year 2: $650$ (Previous year 1 was $550$) $\to 650>550$ (Increase)
* Year 3: $200$ (Previous year 2 was $650$) $\to 200<650$ (Decrease)
* Year 4: $350$ (Previous year 3 was $200$) $\to 350>200$ (Increase)
* Year 5: $700$ (Previous year 4 was $350$) $\to 700>350$ (Increase)
* Year 6: $400$ (Previous year 5 was $700$) $\to 400<700$ (Decrease)

The number of passports issued was more than the previous year in exactly 3 years (Year 2, Year 4, and Year 5).