diff --git a/src/data/backwardsCompatibility/backwardsCompatibility.js b/src/data/backwardsCompatibility/backwardsCompatibility.js
index b08233af9501e2535c0dc8d8c5a9c4006f36f392..b2815968013374580b2013c43b8dec72dcfa422a 100644
--- a/src/data/backwardsCompatibility/backwardsCompatibility.js
+++ b/src/data/backwardsCompatibility/backwardsCompatibility.js
@@ -224,6 +224,9 @@ App.Update.globalVariables = function(node) {
 				V.UI.slaveSummary.abbreviation[key] = V["abbreviate" + capFirstChar(key)] || V.UI.slaveSummary.abbreviation[key];
 			}
 		}
+		if (typeof V.UI.compressSocialEffects !== "number") {
+			V.UI.compressSocialEffects = 0;
+		}
 	}
 
 	if (typeof V.taitorWeeks !== "undefined") {