public async Task <List <CostUsageResponse> > GetCurrentYearCost(CostUsageRequest costUsageRequest)
        {
            var cacheKey = CacheHelpers.GenerateCacheItemKeyForYear(costUsageRequest);

            return(await cache.GetOrCreateAsync(cacheKey, async entry =>
            {
                entry.AbsoluteExpirationRelativeToNow = CacheHelpers.absoluteExpirationRelativeToNow;
                return await costExplorerOperations.GetCurrentYearCost(costUsageRequest);
            }));
        }