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
end