A market with an HHI of less than 1,500 is considered to be a competitive marketplace, an HHI of 1,500 to 2,500 to be a moderately concentrated marketplace, and an HHI of 2,500 or greater to be a highly concentrated marketplace. But there is a few limitation for the HHI Index. The majority  limitation of it is that the firm in specific areas of the country has a monopoly within the specific marketplace in which it does business. For example, after merger of Sprint and T-Mobile, it has increased hundreds HHI in this country, but as for it is in certain geographical areas, so the HHI value will more than 1000 in the actual market.