  We present a multi-instrumental, multidecadal analysis of the activity of the
Eta-Aquariid and Orionid meteor showers for the purpose of constraining models
of 1P/Halley's meteoroid streams. The interannual variability of the showers'
peak activity and period of duration is investigated through the compilation of
published visual and radar observations prior to 1985 and more recent
measurements reported in the International Meteor Organization (IMO) Visual
Meteor DataBase, by the IMO Video Meteor Network and by the Canadian Meteor
Orbit Radar (CMOR). These techniques probe the range of meteoroid masses from
submilligrams to grams. The Eta-Aquariids and Orionids activity duration,
shape, maximum zenithal hourly rates (ZHR) values, and the solar longitude of
annual peaks since 1985 are analyzed. When available, annual activity profiles
recorded by each detection network were measured and are compared. Observations
from the three detection methods show generally good agreement in the showers'
shape, activity levels, and annual intensity variations. Both showers display
several activity peaks of variable location and strength with time. The
Eta-Aquariids are usually two to three times stronger than the Orionids, but
the two showers display occasional outbursts with peaks two to four times their
usual activity level. CMOR observations since 2002 seem to support the
existence of an ~12 year cycle in Orionids activity variations; however,
additional and longer term radar and optical observations of the shower are
required to confirm such periodicity.
