According to Allears, both are listed as high if you consider March 8-14 mid-March.
http://allears.net/pl/attend.htm
Disney states:
The Lowest Attendance --
January (except New Year's Day) until just prior to Presidents' Week in February
The week following Labor Day until the week prior to Thanksgiving
The week following Thanksgiving until mid-December
More Moderate Attendance:
After Presidents' week in February through early March
Late April through early June (except Memorial Day weekend)
Columbus Day Weekend (October)
The first part of Thanksgiving week
Highest Attendance:
Presidents' week in February
Mid March through Late April ("Spring Break")
Memorial Day weekend
Mid June through Labor Day
Thanksgiving Day and weekend
Christmas week through New Year's Day