Phoenix Sky Harbor International Airport has dropped this year in the rankings of America’s most connected airports. The annual report is conducted by the Official Airline Guide (OAG).

Sky Harbor has slipped from No. 9 to No. 12, according to the findings in the annual 2019 Airport Megahubs study.

Both Sky Harbor and Honolulu Airport saw the largest declines from a year ago.

The rankings are based on the ratio of possible scheduled connections to the number of destinations served by that airport. Each airport is assigned a score. Sky Harbor scored 86 in the 2019 report, down from 95 a year ago.

According to John Grant, a senior analyst with OAG, the main reason for Sky Harbor’s decline is competitive development and the fact that other airports have attracted new services and connectivity.

“Phoenix has the same number of destinations served as last year and some other airports have added new airlines and new markets,” Grant said. “The impact that just one or two destinations added each year can be significant; especially when served perhaps more than three times a day as the multiplier impact of connectivity works more favorably.”

Sky Harbor serves as a hub for American Airlines Group Inc. which accounts for about 50% of the airport’s business. American said it will add a number of new destinations to Sky Harbor later this year, but the carrier will be use Phoenix as more of a destination hub rather than a connector.

The OAG report also revealed the 50 most connected international airports. Sky Harbor did not place on this list. Heathrow Airport in London landed the No.1 spot on this list. Sky Harbor has two daily nonstop flights to Heathrow.

Click here to read some of OAG’s other Top 10 Lists.