“Why did the girl sit on her watch?”/“She wanted to be on time.”

A watch riddle is:
 
Q: Why did the girl sit on her watch?
A: She wanted to be on time.
 
The joke has been cited in print since at least 1976.
 
       
Google Books
Biggest Riddle Book in the World
By Joseph Rosenbloom  
Illustrations by Joyce Behr
New York, NY: Sterling Publishing Company, Inc.
1976
Pg. 202:
Why did the girl sit on her watch?
She wanted to be on time.
 
23 December 1979, Indianapolis (IN) Star, “Riddle Box,” sec. 8, pg. 14, col. 5:
Why did the girl sit on her watch?
She wanted to be on time.
 
5 July 1983,  St. Louis (MO) Post-Dispatch, “Jokes by You,” pg. 5D, col. 1:
Q: Why did the girl sit on her watch on the way to school?
A: She wanted to be on time.
Kevin Cook
 
6 March 1992, The News Journal (Wilmington, DE), “Just for Laughs,” 55 Hours sec., pg. 13, col. 5:
Q. Why did the girl sit on her watch?
A. Because she wanted to be on time.
Kim Arandia, age 9
Glasgow
 
23 February 1997, Newsday (Long Island, NY), Kidsday sec., pg. 1:
JOKE OF THE WEEK
Why did the girl want to sit on her watch?
She wanted to be on time.
- Stephanie Lagoudis, Williston Park
 
Google Books
1001 More Cool Jokes with Glen Singleton
By Barb Whiter and Glen Singleton
Victoria, Australia: Hinkler Book Distributors
2002
Pg. 139:
Why did the boy sit on his watch?
He wanted to be on time.
     
29 December 2004, Newsday (Long Island, NY), Kidsday sec., pg. B13:
Why did the boy sit on his watch?
He wanted to be on time.
- KRISTINA SCHROETER,
AGE 13, SAYVILLE
 
Twitter
Louis‏
@islapyou
#doylejoke why did the boy sit on his watch? He wanted to be on time.
7:57 AM - 24 Apr 2009
 
Twitter
Lucky Score‏
@LuckyScoreNet
Why did the girl sit on her
watch?
She
wanted to be on time.
#Joke from #TimeJokes in #Jokes, #Humor and #Satire
9:32 AM - 22 Oct 2017