Hi All,
I am using a panel data consisting of 5 waves. The corresponding year and waves are as follows:

year wave

2008 1
2010 2
2012 3
2014 4
2017 5


I have missing values in the age variable across waves as shown in the sample below: Is there a way or code that can assist me to fill in the missing values for the age variable. With a single observation on the age variable, I can determine what the values should be for the other waves, but I can't do these manually with over 60000 observations. Thanks in advance.

Code:
* Example generated by -dataex-.    To    install:    ssc    install    dataex
clear
input long pid float(wave age)
401011 1  8
401011 2 10
401011 3 12
401011 4 14
401012 1 14
401013 1  9
401013 2 11
401013 3 13
401014 1  3
401014 2  5
401014 3  7
401014 4  9
401014 5 12
401015 1 13
401015 2 15
401016 1  5
401016 2  7
401016 3  9
401016 4 11
401016 5 14
401017 1  7
401017 2  9
401017 3 11
401017 4 13
401018 1  3
401018 2  .
401018 3  7
401018 4  9
401018 5 12
401019 1 10
401019 2 12
401019 3 14
401020 1  2
401020 2  4
401020 3  6
401020 4  8
401020 5 11
401021 1  7
401021 2  9
401021 3 11
401021 4 13
401022 1  7
401022 2  9
401022 3 11
401022 4 13
401023 1  3
401023 2  5
401023 3  7
401023 4  9
401023 5 12
401024 1  1
401024 2  3
401024 3  5
401024 4  7
401024 5 10
401025 1 14
401026 1  8
401026 2  .
401026 3 12
401026 4 14
401027 1 11
401027 2  .
401027 3 15
401028 1  5
401028 2  7
401028 3  9
401028 4 11
401028 5 14
401030 1  1
401030 2  3
401030 3  5
401030 4  7
401030 5 10
401031 1 10
401031 2 12
401031 3 14
401032 1  2
401032 2  4
401032 3  6
401032 4  8
401032 5 11
401033 1 11
401033 2 13
401033 3 15
401034 1 10
401034 2 12
401034 3  .
401035 1  1
401035 2  3
401035 3  .
401035 4  .
401035 5 10
401036 1  5
401036 2  7
401036 3  9
401036 4 11
401036 5 14
401037 1  3
401037 2  5
401037 3  7
401037 4  9
401037 5 12
401038 1  3
401038 2  5
401038 3  7
401038 4  9
401038 5 12
401039 1  9
401039 2 11
401039 3 13
401039 4 15
401040 1  5
401040 2  7
401040 3  9
401040 4 11
401040 5 14
401041 1  9
401041 2 11
401041 3 13
401042 1  8
401042 2 10
401042 3 12
401042 4 14
401043 1  1
401043 2  3
401043 3  5
401043 4  7
401043 5 10
401044 1  6
401044 2  8
401044 3 10
401044 4 12
401044 5 15
401045 1  1
401045 2  3
401045 3  5
401045 4  7
401045 5 10
401046 1  7
401046 2  9
401046 3 11
401046 4 13
401047 1  7
401047 2  9
401047 3 11
401047 4 13
401048 1  2
401048 2  4
401048 3  6
401048 4  8
401048 5 11
401050 1  4
401050 2  6
401050 3  8
401050 4 10
401050 5 13
401051 1 13
401052 1  5
401052 2  7
401052 3  9
401052 4 11
401052 5 14
401053 1 11
401053 2 13
401054 1 15
401056 1  6
401056 2  8
401056 3 10
401056 4 12
401056 5 15
401058 1 15
401059 1 13
401060 1  9
401060 2 11
401060 3 13
401061 1 13
401064 1  3
401064 2  5
401064 3  7
401064 4  9
401064 5 12
401065 1  4
401065 2  .
401065 3  8
401065 4 10
401065 5 13
401066 1  5
401066 2  .
401066 3  9
401066 4 11
401066 5 14
401067 1 13
401068 1  2
401068 2  4
401068 3  6
401068 4  8
401068 5 11
401069 1  9
401069 2 11
401069 3 13
end