hello every one. I am using on cross-section data . but when I run regression I receive this error: insufficient observations
r(2001);"
this is my data
Code:
Country    birth    unen    AverageofC1_Schoolclosing    AverageofC2_Workplaceclosing    AverageofC3_Cancelpubliceven    AverageofC4_Restrictionsonga    AverageofC5_Closepublictrans    AverageofC6_Stayathomerequi    AverageofC7_Restrictionsonin    AverageofC8_Internationaltrav    AverageofE1_Incomesupport    AverageofE4_Internationalsupp    AverageofH1_Publicinformation    AverageofH7_Vaccinationpolicy    AverageofStringencyIndex    AverageofEconomicSupportIndex    GDP_annualgrowth    GDP_percappita    id    lngdp_per
AUT    6714.3333    5.5666667    1.7358423    2.1125448    1.8709677    3.8709677    .65555556    1.827957    1.0003584    3    2    30107.527    2    .10752688    68.294821    96.505376    -6.997    48105.4    1    10.78115
BEL    9052.3333    5.8333333    1.1989247    2.3222222    1.6555556    4    0    1.6129032    0    3    1.8709677    0    2    .04301075    58.400928    87.903226    -6.924    44594.4    2    10.70536
BGR    4542.6667    5.3333333    1.7322581    1.7741935    1.3777778    2.4516129    0    0    0    3    1.9139785    0    2    .05376344    46.806785    63.306452    -4    9975.8    3    9.207917
CHL    13623    11.01472    3    3    2    3.6333333    1.3666667    3    2    3.1125448    2    0    2    .08602151    79.477097    100    -4.486    13231.7    4    9.490371
CZE    8648.6667    3.0666667    2.3286738    1.6129032    1    3.9139785    0    1.3333333    1.7741935    3    2    8699.5044    2    .10752688    64.140993    62.5    -6.5    22762.2    5    10.03286
DNK    4848.6667    5.9666667    1.1512545    1.344086    1.2473118    3.6129032    .09677419    .7483871    .11111111    3    1.8817204    0    2    .10752688    46.564563    90.793011    -6.5    60908.8    6    11.01713
EST    1004    7.2666667    1.3870968    1.2150538    1.2150538    2.5    0    0    0    3    0    0    2    .05376344    41.784892    50    -7.5    7143.2    7    8.873916
FIN    3731    8.1333333    1.311828    1.3444444    1.4222222    3.0218638    0    .2688172    0    3    2    0    2    .05376344    42.880054    75    -6.031    49041.3    8    10.80042
HUN    7537.6667    4.2    1.5666667    1.6444444    1.5666667    3.1333333    .64444444    1.2444444    0    4    .56666667    0    2    .06451613    59.710556    32.083333    -3.1    15899.1    9    9.674018
ISL    355    7    1    1.7956989    1.7956989    3.6344086    0    0    0    3    2    0    2    .06451613    49.543011    89.38172    -7.206    59260.9    10    10.98971
ISR    14927.333    4.7606197    2.3010753    2.344086    1.9236559    3.2903226    .47311828    1.8473118    1.8473118    2.7408602    1.7408602    0    2    .41935484    71.300538    77.688172    -6.288    43610.5    11    10.68305
ITA    33060.333    9.9333333    1.7634409    2.578853    2    3.7096774    .76344086    1.5268817    1.5268817    3    1    0    2    .10752688    71.903262    75    -9.134    31676.2    12    10.36332
KOR    20499.667    4.3    1.5609319    1.2258065    1.6802867    3.2716846    0    1    2    2.0967742    1    0    2    0    57.422907    50    -1.178    31489.1    13    10.3574
LTU    1902.3333    9.2333333    2.172043    2.0860215    1.827957    3.827957    .31397849    1.172043    .88172043    2.1182796    1    0    1    .09677419    56.465548    62.5    -8.086    19997.6    14    9.903368
LVA    1324.3333    8.0666667    1.8494624    1.8709677    1.2222222    3.5053763    0    .04301075    0    2.2365591    1.0888889    0    2    .04301075    47.603154    77.222222    -8.608    17620    15    9.77679
NLD    13729.667    4.0666667    1.344086    2.3827957    2    4    .1827957    1    .74946237    3    2    0    2    0    64.352817    75    -7.493    52304.1    16    10.86483
PRT    6835.6667    7.2333333    1.2831541    2    2    4    1    1.5268817    .10896057    3    1    0    2    .10752688    63.966197    75    -8    22439.9    17    10.0186
ROU    13093    5.1333333    2.7956989    1.9354839    1.7179211    3.5777778    .07777778    1.537276    1    2.9139785    2    0    2    .05376344    64.555262    86.693548    -5    12896.1    18    9.464681
SWE    8467    8.6333333    1.2688172    1.4111111    2    3.4111111    1    1    .56666667    3    2    460098.77    2    .10752688    60.829796    62.5    -6.788    51925.7    20    10.85757
SVN    1493.3333    5.3333333    2.4946237    2    2    3.8064516    .8172043    1.5913978    1.6129032    2.0107527    1.9892473    0    2    .12903226    74.42328    74.731183    -8.039    25179.7    19    10.13379
UKR    24266.667    5.048158    2.8602151    2    1    2.5333333    1.8602151    1    1.7204301    2    1    0    2    0    59.307226    37.5    -7.731    3726.9    21    8.223332
and I use :
Code:
. reg birth unen AverageofC1_Schoolclosing AverageofC2_Workplaceclosing GDP_annualgrowth lngdp_per if id==1
insufficient observations
r(2001);
or even others id of countries
it is cross section just for 2020.

I hope I recieve your advice so soon. thank you .
best regards ,