Issue with my script to store Google spreadsheet data daily - google-apps-script

Question

I've been having trouble getting my scripts to work for my investment portfolio spreadsheet. They were working fine until early May and I've been unable to get them to work since. What I'm trying to do is store the performance of my portfolio each day to a separate sheet. The script should be finding the next empty row and putting the current date in the first column and the value in the 2nd column. What it's doing is overwriting the row each time the script is run.
Here is my script:
function storePerf() {
SpreadsheetApp.flush();
var ss = SpreadsheetApp.getActiveSpreadsheet();
SpreadsheetApp.setActiveSheet(ss.getSheets()["0"]);
var source = ss.getRange ("Performance!G28");
var destSheet = ss.getSheetByName("Performance Historical");
var numRows = source.getNumRows();
var numColumns = source.getNumColumns();
var nextColumn = numColumns +1;
// Determine the first empty row to paste to.
var destRange = destSheet.getRange(destSheet.getLastRow()+1,2);
source.copyTo (destRange, {contentsOnly: true});
// Print date in the cell to the right of the latest price
destSheet.getRange(destSheet.getLastRow(),1).setValue(new Date());
SpreadsheetApp.flush();
}
Any help would be much appreciated.
thanks

Answer 1

Also add the +1. Or add the flush function before. The script is faster then the added row.
SpreadshertApp.flush()
destSheet.getRange(destSheet.getLastRow(),1).setValue(new Date());
But then Isuggest you use appendRow and make it a lot easier:
var source = ss.getRange ("Performance!G28");
var destSheet = ss.getSheetByName("Performance Historical");
//make a new row
var newRow = [source.getValue(), new Date()]
destSheet.appendRow([newRow]);
SpreadsheetApp.flush();