Converting variable "Date" from string to numeric

Hello Forum:

I have a variable named Date and in string format, displayed in the Data Editor as:

Date
Q1 2001
Q2 2001
Q3 2001
Q4 2001
....

Q1 2017
Q2 2017
Q3 2017
Q4 2017

Its type and format are str263 and %263s, respectively.

My question is how to convert Date into a numeric format?

Please note, I've been a heavy user of sas and matlab for a number of years and have just started learning about STATA today. Your help is greatly appreciated.

Thank You
Matthew