Period comparisons compare a metric in your selected time frame e.g. 'This week' against a selected comparison timeframe e.g. 'WoW'. This will compare this week's data against last week's data and calculate a percentage difference between the two figures. 

As a default when we visualise this percentage difference, we show a percentage increase in green and a percentage decrease in red to symbolise a good or bad change over time. 

However, there might be a case where an increase in your current metric over time is actually a negative change and you may want to display this in red. For example, if you have a metric called 'Bounce Rate' which measures the number of users who navigate away from your site after one page view, an increase in this number actually shows a negative impact. 

Similarly, you may have a metric where an increase or decrease in your metric over time does not necessarily reflect a positive or negative change. For example, your cost is usually dependent on a specific budget and can be affected by specific up-weights or down-weights so you may not want to visualise these changes as 'good' or 'bad' as these changes are controlled internally. 

You can change how your metric will be displayed in period comparisons in the Report Engine under 'Uplift Bias' in the metric details section of the metric page.

There are three options in this drop down - Normal, Neutral, Inverse. 

Once these changes have been made you will be able to see the colours correctly reflected in your period comparisons:
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