st: Duplicate observations with equal values (except one value). Add up this value and keep one observation

[miriam geringer <miriam.geringer@gmail.com>]

Hey guys,

in my dataset, there are some entries (duplicate entries), which are
identical (all variables have identical values), EXCEPT one variable.

There is one variable, which has different values. All other variables
have exactly the same variables.

Now, I want to add/sum up these two different values and keep all
other (identical) variables the same. After adding up the different
values, I want to keep only one observation with the summed up value.

Example:

This is how it looks:
PERMNO      dofd (DAILY_ID)           Price            Shares offered
123456             1                                     5
            8
123456             1                                     5
            6

This is how it should be:
PERMNO       dofd(DAILY_ID)           Price             Shares offered
123456              1                                   5
            14

Somethink like: If all variables are the same except variable "shares
offered", sum up this variable and keep one observation.

Can anyone help?

Thanks!
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