请问如何将每个symbol下每year的proportion根据status进行运算,即每个symbol下每year下,status=0的proportion加上status=1的proportion然后减去status=2的proportion.
* Example generated by -dataex-. To install: ssc install dataex
clear
input long symbol float year byte status float proportion
1 2015 0 63.14251
1 2015 1 .184824
1 2015 2 2.297158
1 2015 3 3.10397
1 2016 0 62.92771
1 2016 1 .817774
1 2016 2 2.161083
1 2016 3 2.285065
1 2017 0 60.40708
1 2017 1 5.514133
1 2017 2 1.907036
1 2017 3 3.532766
1 2018 0 62.77109
1 2018 1 3.451947
1 2018 2 1.310863
1 2018 3 1.656923
1 2019 0 62.0994
1 2019 1 9.713852
1 2019 2 .950527
1 2019 3 2.644622
1 2020 0 61.4861
1 2020 1 10.610368
1 2020 2 2.342319
1 2020 3 3.781443
2 2015 0 25.595955
2 2015 1 15.320314
2 2015 2 1.671902
2 2015 3 15.621412
2 2016 0 38.47235
2 2016 1 11.96428
2 2016 2 3.205136
2 2016 3 4.995837
2 2017 0 56.66092
2 2017 1 .722086
2 2017 2 12.803775
2 2017 3 1.715221
2 2018 0 50.24652
2 2018 1 7.944968
2 2018 2 14.464606
2 2018 3 5.71937
2 2019 0 37.56578
2 2019 1 6.691942
2 2019 2 21.90235
2 2019 3 7.851119
2 2020 0 36.670048
2 2020 2 7.856169
2 2020 3 3.967149
2 2020 1 20.616995
4 2015 0 44.76
4 2015 2 .374032
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