Dear Statalist users

I have some activity data which asks respondents how much time they spent in paid work across two variables - one for pre-COVID and the second for during COVID-19, but I would like to merge these two into one variable and then have an indicator for pre- and during-COVID so I can do some modelling on this. I think I need to reshape the data as well. Any suggestions would be most welcome

Best
Brendan

Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input float id double(Q23_1 Q23_2)
100001 0 0
100002 0 0
100003 6 6
100004 0 0
100005 0 0
100006 0 0
100007 4 7
100008 0 0
100009 0 0
100010 0 0
100011 0 0
100012 1 4
100013 1 1
100014 5 6
100015 5 10
100016 4 5
100017 4 6
100018 0 0
100019 0 0
100020 0 0
100021 4 10
100022 0 0
100023 8 10
100024 1 0
100025 2 2
100026 8 10
100027 2 2
100028 4 10
100029 3 7
100030 0 0
100031 0 0
100032 8 10
100033 0 0
100034 4 8
100035 6 10
100036 10 10
100037 0 0
100038 0 0
100039 0 0
100040 3 3
100041 3 3
100042 10 10
100043 0 0
100044 0 0
100045 9 9
100046 6 10
100047 0 0
100048 0 0
100049 0 0
100050 0 0
100051 3 10
100052 3 9
100053 1 3
100054 3 4
100055 2 5
100056 0 0
100057 5 10
100058 3 5
100059 2 2
100060 0 0
100061 3 5
100062 10 10
100063 0 0
100064 0 0
100065 0 0
100066 0 0
100067 4 8
100068 4 7
100069 3 5
100070 10 3
100071 0 0
100072 10 10
100073 10 10
100074 8 8
100075 0 0
100076 2 4
100077 0 0
100078 1 0
100079 2 4
100080 2 2
100081 0 0
100082 5 8
100083 4 10
100084 0 0
100085 2 10
100086 0 0
100087 4 7
100088 8 10
100089 4 6
100090 2 1
100091 10 10
100092 0 0
100093 5 10
100094 0 0
100095 0 0
100096 0 0
100097 3 5
100098 0 0
100099 0 0
100100 6 10
end