diff --git a/browser/src/control/Control.FormulaAutoCompletePopup.ts b/browser/src/control/Control.FormulaAutoCompletePopup.ts
index fe1263f45d913..d81218a005e15 100644
--- a/browser/src/control/Control.FormulaAutoCompletePopup.ts
+++ b/browser/src/control/Control.FormulaAutoCompletePopup.ts
@@ -64,10 +64,22 @@ class FormulaAutoCompletePopup extends L.Control.AutoCompletePopup {
 		if (eventType === 'close') {
 			this.closePopup();
 		} else if (eventType === 'select' || eventType === 'activate') {
-			var currentText = this.map._docLayer._lastFormula;
-			var chIndex = currentText.length - 1;
-			var functionName = this.functionList[index].name;
-			var namedRange = this.functionList[index].namedRange;
+			const namedRange: string = this.functionList[index].namedRange;
+			let currentText: string = this.map._docLayer._lastFormula;
+			if (namedRange) {
+				const openBracketIndex: number = currentText.indexOf('(');
+				const semicolonIndex: number = currentText.indexOf(';');
+				if (semicolonIndex !== -1) {
+					let tmpCurrentText = currentText.substring(semicolonIndex + 1);
+					// trim white space if there is any
+					tmpCurrentText = tmpCurrentText.trim();
+					currentText = ';' + tmpCurrentText;
+				} else if (openBracketIndex !== -1) {
+					currentText = currentText.substring(openBracketIndex);
+				}
+			}
+			const chIndex: number = currentText.length - 1;
+			let functionName: string = this.functionList[index].name;
 			functionName = functionName.substring(chIndex);
 			if (namedRange) this.map._textInput._sendText(functionName);
 			else this.map._textInput._sendText(functionName + '(');