diff --git a/src/events/intro/customizeSlaveTrade.js b/src/events/intro/customizeSlaveTrade.js
index 86bf50310e954784ade5d2c9e1407b9bb7634a69..d989a707968fc64b533a692cab6793b568ebf2e1 100644
--- a/src/events/intro/customizeSlaveTrade.js
+++ b/src/events/intro/customizeSlaveTrade.js
@@ -436,13 +436,13 @@ App.Intro.CustomSlaveTrade = function() {
 	 */
 	function populateFromCoordinates(lat, lon) {
 		V.nationalities = {};
-		for (let gp of App.Data.World.gridPoints()) {
-			const coords = App.Data.World.gridPointToCoordinate(gp);
+		for (const p of App.Data.World.gridPoints()) {
+			const coords = App.Data.World.gridPointToCoordinate(p);
 			const dist = distanceInKmBetweenEarthCoordinates(lat, lon, coords[0], coords[1]);
 			const pop1 = 1; // assume the clicked grid's population is 1. we could look it up, but it doesn't matter (it cancels out during normalization)
-			const pop2 = App.Data.World.populationAt(gp);
+			const pop2 = App.Data.World.populationAt(p);
 			const gravity = (pop1 * pop2) / (dist * dist * frictionForDistance(dist));
-			const nation = App.Data.World.nationAt(gp);
+			const nation = App.Data.World.nationAt(p);
 			addNationality(nation, Math.round(gravity));
 		}
 		refresh();