Like this:
| makeresults | eval item="item 1", count_a=12, count_b=23, count_c=50, date="07/06/2018"
| append [| makeresults | eval item="item 1", count_a=3, count_b=123, count_c=41, date="07/05/2018"]
| append [| makeresults | eval item="item 1", count_a=31, count_b=13, count_c=21, date="07/04/2018"]
| append [| makeresults | eval item="item 2", count_a=1, count_b=42, count_c=12, date="07/04/2018"]
| append [| makeresults | eval item="item 2", count_a=21, count_b=142, count_c=122, date="07/05/2018"]
| table date item count_a count_b count_c
| eval _time = strptime(date, "%m/%d/%Y")
| sort 0 _time
| streamstats current=f last(count*) AS prev_count* BY item
| foreach count* [ eval diff<<MATCHSTR>> = <<FIELD>> - prev_count<<MATCHSTR>> ]
... View more