\\How we can generate the dummy variable: for January
\\ We observed that the format "Month" variable is year+month i.e 196001 is year=1960 and month is 01 (January)
\\we are  therefore interested in the last two digits of this variable
\\ First step: You need to change the type of data from numeric to be the string 
 gen monthnew3 = string(month)
 \\ Now, create the new variable that is based on the last two digits, since there are 6 placements on the number 196001, we then using only the 5th and 6th placements 
 gen jan3 =substr(monthnew3,5,6)
 \\then jan3 is the new string with the last two digits
 \\we need to covert the string to be the numeric again
 destring jan3, generate(jan4)
 \\ using the condition to create the new dummy variable i.e.  the value =1 if the number=01 (January) otherwise we put zero
gen dummy1=1 if jan4==1
replace dummy1=0 if missing(dummy1)