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The distribution of solar system absolute magnitudes ($H$) for the near-Earthasteroids (NEAs) observable near opposition -- i.e. Amors, Apollos, and Atens($A^3$) -- is derived from the set of ALL currently known NEAs. The result isbased only on common sense assumptions of uniformly random distributions andthat the orbital phase space and $H$-magnitude distribution of known NEAs isrepresentative of the total population. There is no population or othermodeling and no assumption on albedo except in interpreting the result as asize-frequency distribution (SFD). The analysis is based on the 18355 $A^3$NEAs cataloged by the MPC as of June 2018. The observations from 9 of the topprograms (in terms of number of distinct NEAs observed) and the smaller butdeeper DECam NEO Survey are used, comprising 74696 measurements of 13466 NEAsobserved within 30 deg of opposition. The only parameter in the analysis is anestimate of the detection magnitude limits for each program.  A single power-law slope for the cumulative distribution,$\log(N<H)=0.50\pm0.03H$, for $H < 27$ is found with no evidence for additionalstructure. A turn-over fainter than 27th magnitude may occur, but thepopulation of known NEAs is dropping off rapidly because they are difficult todetect and so possibly is a completeness effect. Connecting to the nearlycomplete census of the brightest/biggest NEAs (diameter $> {\sim}2$Km) providesa normalization that estimates ${\sim}10^8 A^3$ NEAs with $H < {\sim}27$corresponding to NEAs greater than ${\sim}10$m in diameter for reasonabletypical albedos.  Restricting the analysis to Earth crossing asteroids (10839 known, 7336selected, 36541 observed) produces the same power-law slope.

A New Method for Estimating the Absolute Magnitude Frequency Distribution of Near Earth Asteroids (NEAs)