How to add multiple duration from multiple independent transactions

So I am running multiple single valued transactions and putting the values in eval keywords, but I want to add all these new values to get the total value (duration1+duration2+....) and show it in another panel. Here is my following transactions I am running. They are all run separate inside a single row index=main host=host1 | transaction startswith="keyword1" endswith="keyword1_ending" | eval keyword1_duration = duration | stats sum(keyword1_duration) index=main host=host1 | transaction startswith="keyword2" endswith="keyword2_ending" | eval keyword2_duration = duration | stats sum(keyword2_duration) how do I add these values ? Do I have to define a token on each block to use that value across panels ?