Hi every body,,,

Currently i am conducting study to evlaute the productivty and the tehcnical efficiency of 18 public hospitals (DMUs) from 2010 to 2018, using DEA Malmaquist Productivty Index

i have creat a panel data in excel and then transfered it to stata 16 (attached)
DMU Year Beds Annual Recurrent Expenditure No. of Inpatient Days/year No. of Outpatient visitis/year
1 2010 623 41.1 151445 155,481
2 2010 485 18.3 110,110 159,438
3 2010 142 9 21,900 147,474
4 2010 450 11.8 103,660 308,897
5 2010 100 1.6 10,220 12,188
6 2010 150 2.5 23,360 247,933
7 2010 301 8.8 62,780 158,004
8 2010 363 11.8 89,790 217,004
9 2010 235 7.2 57,670 145,057
10 2010 243 6.4 36,500 95,488
11 2010 191 6.1 48,545 71,948
12 2010 240 7.2 51,100 140,748
13 2010 40 0.6 6,205 27,662
14 2010 70 2.1 12,045 30,193
15 2010 94 3.3 14,235 219,728
16 2010 60 1.7 12,775 219,096
17 2010 80 2.1 18,980 41,332
18 2010 89 2.6 18,615 268,449
1 2011 623 51.3 142,349 169,807
2 2011 491 21.1 118,103 143,551
3 2011 134 10.2 25,550 155,636
4 2011 450 13.9 110,595 302,023
5 2011 100 1.9 9,855 10,235
6 2011 150 3.4 21,170 118,821
7 2011 301 10.1 63,875 160,023
8 2011 363 12.5 93,075 192,750
9 2011 235 8.1 60,590 135,531
10 2011 243 7.4 41,610 99,898


i used the following step:
1- xtset dmu year to verify the panal set and time
then i used the following command

malmq2 beds annualrecurrentexpenditure = noofinpatientdaysyear noofoutpatientvisitisyear,ort(i)period( year) trace

but i recived this error (option period() not allowed), so i really appreciat if anyone can help me with this issues

kind regards