Hello, I have a dataset that contains several executive's compensation infromation for each company. However, since each company have several top executives for each year, I want to ask how to count each company has how many years of data?
I want to delete the firms that have less than 5 years of data.

Thank you!

Below is my data sample:
[CODE]
* Example generated by -dataex-. To install: ssc install dataex
clear
input long gvkey int year float option_awards_fv long execid
1004 2010 668.254 9249
1004 2010 192.458 33979
1004 2010 158.8 36199
1004 2010 192.458 41787
1004 2010 322.872 9252
1004 2011 0 36199
1004 2011 166.592 41787
1004 2011 166.592 33979
1004 2011 279.483 9252
1004 2011 578.46 9249
1004 2012 83.462 19999
1004 2012 347.76 9252
1004 2012 208.656 41787
1004 2012 208.656 33979
1004 2012 695.52 9249
1004 2012 120.75 44858
1004 2013 486.605 41787
1004 2013 811.008 9252
1004 2013 1622.016 9249
1004 2013 281.6 44858
1004 2013 194.642 19999
1004 2013 458.424 46404
1004 2014 0 9249
1004 2014 0 41787
1004 2014 0 48195
1004 2014 0 9252
1004 2014 0 46404
1004 2015 0 48195
1004 2015 0 9249
1004 2015 0 9252
1004 2015 340 46404
1004 2015 0 19999
1004 2015 312 41787
1004 2017 308.228 9252
1004 2017 47.277 51706
1004 2017 1483.2 9249
1004 2017 98.644 55405
1004 2017 0 41787
1004 2017 1300.118 48195
1004 2018 250.161 55405
1004 2018 125.081 51706
1004 2018 2014.961 48195
1004 2018 349.952 41787
1004 2018 0 57007
1013 2010 656.602 10203
1013 2010 156.6 25854
1013 2010 114.318 40581
1013 2010 106.488 30717
1013 2010 140.94 32376
1045 2010 458.222 16654
1045 2010 1185.94 14591
1045 2010 661.628 26059
1045 2010 458.222 28280
1045 2010 329.848 28279
1045 2010 329.848 41119
1045 2011 175.511 28279
1045 2011 308.187 16654
1045 2011 441.045 26059
1045 2011 175.511 41119
1045 2011 308.187 28280
1045 2011 798.6 14591
1045 2012 0 41119
1045 2012 0 16654
1045 2012 0 44119
1045 2012 0 28279
1045 2012 0 26059
1045 2013 0 46193
1045 2013 0 46191
1045 2013 0 44119
1045 2013 0 26059
1045 2013 0 41119
1045 2013 0 16654
1045 2013 0 46192
1045 2013 0 46190
1045 2013 0 46189
1045 2014 0 46192
1045 2014 0 46193
1045 2014 0 46190
1045 2014 0 46189
1045 2014 0 46191
1045 2015 0 46193
1045 2015 0 46189
1045 2015 0 46192
1045 2015 0 46190
1045 2015 0 46191
1045 2016 0 46192
1045 2016 0 51368
1045 2016 0 46189
1045 2016 0 46193
1045 2016 0 46190
1045 2016 0 46191
1045 2017 0 46193
1045 2017 0 46189
1045 2017 0 51368
1045 2017 0 46191
1045 2017 0 46190
1045 2018 0 51368
1045 2018 0 46189
1045 2018 0 46191
1045 2018 0 46192