diff --git a/R/impact_inference.R b/R/impact_inference.R
index 301b907..4d4ffbb 100644
--- a/R/impact_inference.R
+++ b/R/impact_inference.R
@@ -246,10 +246,10 @@ CompileSummaryTable <- function(y.post, y.samples.post,
       AbsEffect.sd = c(sd(rowMeans(y.repmat.post - y.samples.post)),
                        sd(rowSums(y.repmat.post - y.samples.post))))
   summary <- dplyr::mutate(summary,
-                           RelEffect = AbsEffect / Pred,
-                           RelEffect.lower = AbsEffect.lower / Pred,
-                           RelEffect.upper = AbsEffect.upper / Pred,
-                           RelEffect.sd = AbsEffect.sd / Pred)
+                           RelEffect = AbsEffect / abs(Pred),
+                           RelEffect.lower = AbsEffect.lower / abs(Pred),
+                           RelEffect.upper = AbsEffect.upper / abs(Pred),
+                           RelEffect.sd = AbsEffect.sd / abs(Pred))
   rownames(summary) <- c("Average", "Cumulative")
 
   # Add interval coverage, defined by alpha