The logic appears correct, but why multiply by 100?
Save yourself a step:
| inputlookup sample.csv
| eval isananomaly = if((Failcount / Totalcount) > .04 , 1 , 0)
from User warren – Stack Overflow https://stackoverflow.com/questions/64249711/splunk-enterprise-i-am-trying-to-calculate-results-where-if-4-of-failure-is-a/64262356#64262356
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