This will allow you to use the Date filters at the top of the Report Screen:
SELECT
[InventoryItemName] as [Item]
, sum([Consumption]) as [Consumed]
FROM [PeriodicConsumptionItems] i
left join [PeriodicConsumptions] p on p.[Id]=i.[PeriodicConsumptionId]
WHERE 1=1
--and p.[StartDate] >= '2015-01-01'
--and p.[EndDate] <= '2015-01-31'
and p.[StartDate] >= '{Start}'
and p.[EndDate] <= '{End}'
GROUP BY [InventoryItemName]
ORDER BY [InventoryItemName]