private IEnumerable <Price> GetNewPrices(IEnumerable <Price> allPrices)
{
var lastPrices = PriceRepository.GetLastPrices().ToList();
return(allPrices
.Where(i => (lastPrices
.Any(l => l.MarketId == i.MarketId && l.Value != i.Value) ||
(lastPrices.All(l => l.MarketId != i.MarketId)))).ToList());
}
