DESK strives to replicate a US index focused on office and commercial real estate investment trusts (REITs). REITs must satisfy market cap and revenue criteria to be eligible for inclusion. They are then ranked via a two-step process, each relying on the free-float market cap and three-month average daily trading volume of the stocks respectively. Securities are then grouped within Office and Commerical REITS and ranked again based on the sum of their ranks in each of the categories mentioned above. The top 25 Office REITs constitute the index, complemented by the top Commerical REITS if needed. The index maintains a target coverage of 25 companies at all times. It also follows a range tiered modified float-adjusted market-cap weighting scheme, capping security weight at 10% and the aggregate weight of Other Commerical REITs at 20%. A 5%-50% rule is also imposed to ensure diversification. The index undergoes quarterly rebalancing and semi-annual reconstitution.