...- As long as a successful medical therapy for COVID-19 is introduced by mid-2021, enabling business and group travelers to begin to feel safe to travel again, we believe Marriott International Inc. can ramp up systemwide revenue per available room (RevPAR), EBITDA, and cash flow from operations and begin to reduce debt balances. However, we believe the recovery in business and group travel and hotel demand will be slower than we expected a few months ago, and may not take hold until the second half of 2021. - We are affirming Marriott's '###-' issuer credit and senior unsecured ratings because we expect adjusted leverage will decline comfortably below our 4.25x downgrade threshold by 2022 and believe the company's business and financial strengths warrant looking out this far, as long as incremental risk factors do not materialize. We are removing our ratings on the company from CreditWatch, where we placed them with negative implications on April 2, 2020. - The negative outlook reflects...