LS has one powerful chart. It is line-diagram. It can show more than 2 column data.
I have developed SQL-query for BIOS and Monitor Ages. It have to be used with this type chart.
You should use report's name with prefix "Chart:".
Chart: BIOS and Monitor Ages
Query:
Select Top 1000000 Coalesce(monitor_t.MonitorYear, bios_t.BiosYearReleased) As
ReleasedYear,
Coalesce(monitor_t.TotalM, 0) As monitor_count,
Coalesce(bios_t.TotalB, 0) As bios_count
From (Select DatePart(yyyy, tblMonitor.ManufacturedDate) As MonitorYear,
Count(tblMonitor.MonitorID) As TotalM
From tblMonitor
Where DatePart(yyyy, tblMonitor.ManufacturedDate) <> 1990
Group By DatePart(yyyy, tblMonitor.ManufacturedDate)) monitor_t
Full Join (Select DatePart(yyyy, tblBIOS.ReleaseDate) As BiosYearReleased,
Count(tblAssets.AssetID) As TotalB
From tblAssets
Inner Join tblBIOS On tblAssets.AssetID = tblBIOS.AssetID
Group By DatePart(yyyy, tblBIOS.ReleaseDate)) As bios_t On
monitor_t.MonitorYear = bios_t.BiosYearReleased
Order By ReleasedYear
After create report you can add Chart Report on Tab via drag&drop it

Choose line-type and show label. My result:
