Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Changes in SWAP MS between years for all eyes. Changes greater than +11 dB or less than −11 dB are censored at those limits for ease of viewing, except in the last histogram showing changes over the entire series (hence the different horizontal scale on that histogram).
