MPA Film Rating System

1967–1968
This needs expansion. Anyone willing can expand this.

1968–1970
Originally, there were 4 ratings. G was all audiences, all ages. M was all audiences, but parental discretion was advised. R was for people ages 16 and up unless under 16 and accompanied by someone. X was for adult films. Nobody under 18 was permitted for X films.

1970–1972
In 1970, the system changed. M was changed to GP. R was changed from under 16 to under 17 for adult accompaniment. X now lets 17 year olds in.

1972–1984
PG replaces GP, but have the same rules.

1984–1990
In 1984 PG-13 was added, closing the gap between PG & R.

1990–present
NC-17 replaces X, and still uses the rules X did.

1990–1996
First use of NC-17, with 17 and older only allowed.

1996–2013
In 1996, NC-17 was raised back to 18 minimum for age.

2013–present
New designs with descriptions replaced the 17-year-old previous rating designs.