The charts on MetaTrader 4 reflect the "Bid" price only, the "Ask" price is not shown on the charts. You can however draw an "Ask" line on the charts by clicking on the chart and selecting 'show ask line', this will result in an estimation of the "Ask" price which is based entirely on the spread. You should bear this in mind when conducting any historical analysis using the charts available in MetaTrader 4.