Sundays in February

A February has $5$ Sundays only if it has $29$ days and starts on a Sunday. How often does the weekday of a leap-year February $1$ repeat?

1. February has $5$ Sundays only if it has $29$ days and the $1$st of February is a Sunday, so only leap years count; $1900$ is not a leap year and $2000$ is.
2. Between $1900$ and $2099$ the leap years follow every $4$ years without a skipped one except $1900$, so the weekday of February $1$ in leap years repeats with period $28$ years.
3. The first leap year in the range with February $1$ on a Sunday is $1920$, and then come $1948$, $1976$, $2004$, $2032$, $2060$ and $2088$.
4. Counting these years gives $7$.

Answer: $7$