If your goal is to get 99.9% modeling quality in MetaTrader 4/5, several apps act as automated bridges: Forex Historical Data Feed :: Dukascopy Bank SA
A decade of tick data for the EUR/USD pair can exceed several gigabytes in raw format. Standard spreadsheets like Excel cannot handle this volume; traders must use specialized databases like SQL or high-performance languages like Python (Pandas) and C++. Format Conversion dukascopy+historical+data