Moody’s Investors Service has affirmed the University of Chicago Medical Center’s (UCMC) bond ratings and raised its bond ratings outlook from “negative” to “stable.”

Moody’s affirmation of the UCMC’s Aa3 rating, its fourth-highest rating, and its revision of the rating outlook to “stable” come as good news to the UCMC after Moody’s threatened a rating downgrade in both its 2013 and 2014 reports.

The new report indicates that the investor service remains confident that the UCMC poses a very low credit risk despite its $693 million of rated outstanding debt.

The outlook revision to “stable” reflects UCMC’s improvements in operating margins in the 2014 and 2015 fiscal years and UCMC’s maintenance of a strong relationship with the University of Chicago, which holds Moody’s third-highest rating, Aa2.

Moody’s report states that the rating could rise if the University of Chicago gives the UCMC more “explicit support,” and that a weakening of the relationship could prompt a rating downgrade.

The report cited three key metrics for the UCMC’s upcoming fiscal years that will determine future ratings: operating margins (income divided by costs of operation), liquidity ratios (cash assets divided by short-term debts), and debt pay downs (the difference between debts repaid and new loans taken out). Ashley Heher, a spokeswoman for UCMC, said UCMC does not “comment on specific ratings or the assessment of our outlook from a rating agency” but remains “committed to providing the highest standards of quality and safety in the care we provide our patients.”