The Centers for Disease Control and Prevention has big news when it comes to cancer in children: brain cancer is now the No. 1 cause of mortality, knocking leukemia off the top spot. And this is actually good news — why? Because the report found that cancer rates are actually plunging, and the shakeup is part of the reason why brain cancer vaulted to the top spot.

The CDC found that leukemia, which had been the number one risk to children, had declined to No. 2 with brain cancer moving into the top spot. This is based on data between 1999 and 2014. Overall, cancer rates declined significantly, and while brain tumors remained a big problem, they aren’t becoming more common in children, according to a CDC statement.

Better detection methods and improved treatments have driven down the mortality rates of leukemia in children. The death rate from cancer overall dipped 20 percent among children and teens over the 15-year period. Brain tumors and leukemia still made up more than half of all cancer deaths in children despite the drop. Brain cancer hasn’t seen quite as many advancements in technology and treatments over the years.

From the CDC statement: “Since the mid-1970s, cancer death rates among children and adolescents in the United States showed marked declines despite a slow increase in incidence for some of the major types (1–3). These trends have previously been shown through 2012. This data brief extends previous research by showing trends in cancer death rates through 2014 among children and adolescents aged 1–19 years in the United States. Cancer death rates for 1999–2014 are presented and trends are compared for both females and males, by 5-year age group, and for white and black children and adolescents. Percent distributions of cancer deaths among children and adolescents aged 1–19 years are shown by anatomical site for 1999 and 2014.”