Format axis labels as dates or currencies in a paginated report (Report Builder)
Applies to: 
Microsoft Report Builder (SSRS)
Power BI Report Builder
Report Designer in SQL Server Data Tools
When you show properly formatted DateTime values on an axis in a paginated report, a chart will automatically display these values as days. To specify a date/time interval for the x-axis, such as an interval of months or an interval of hours, you must format the axis labels and set the type of axis interval to a valid date or time interval.
Note
In column and scatter charts, the horizontal, or x-axis, is the category axis. In bar charts, the vertical, or y-axis, is the category axis.
In order to format time intervals correctly, the values displayed on the x-axis must evaluate to a DateTime data type. If your field has a data type of String, the chart will not calculate intervals as dates or times. For more information, see Charts (Report Builder and SSRS).
When a numeric value is added to the y-axis, by default, the chart does not format the number before displaying it. If your numeric field is a sales figure, consider formatting the numbers as currencies to increase the readability of the chart.
Note
You can create and modify paginated report definition (.rdl) files in Microsoft Report Builder, Power BI Report Builder, and in Report Designer in SQL Server Data Tools.
To format x-axis labels as monthly intervals
Right-click the horizontal, or x-axis, of the chart, and select HorizontalAxis Properties.
In the HorizontalAxis Properties dialog box, select Number.
From the Category list, select Date. From the Type list, select a date format to apply to the x-axis labels.
Select Axis Options.
In Interval, type 1. In Interval type property, select Months.
Note
If you do not specify an interval type, the chart will calculate intervals in terms of days.
Select OK.
To format y-axis labels using a currency format
Right-click the vertical, or y-axis, of the chart, and select VerticalAxis Properties.
In the VerticalAxis Properties dialog box, select Number.
From the Category list, select Currency. From the Symbol list, select a currency format to apply to the y-axis labels.
Select OK.