Of " how far edge you go? 1997
Some data on Ho:

These values are obtained by various tests, see the site " how far edge you go?"
for more precise details: http://astro.u-strasbg.fr/howfar97.html.
Nature of the test Ho Remarks
diameter of the galaxies 52 + - 6 + - 8 uncertainties + - local uncertainties
Tully-Fisher relation 55 + - 5 without the corrections related to " Hipparcos "
Tully-Fisher relation 49 + - 6 with the corrections related to " Hipparcos "
distance for Virgo 55 + - 9 methods
distance for Virgo 56 + - 7 independent
supernovas 58 + 7 -8 use of the cepheids
"sosies" of Andromeda 53 +-8 with the Tully-Fisher relation

The " average " of these values obtained by " traditional " methods is Ho=54 + - 9. (this " average " does not have any mathematical meaning).
There are new not very precise methods for the moment like that based on the " lens gravitational " effect or on the " Sunyaev-Zel'dovich " effect.
And then there are the problem of possible bias for any methods and the problem of uncertainties on the primary indicators of distances (cepheids). Always it is that in a few years, the precision on the Ho value increased considerably.


There remains the big problem of the determination of the density parameter.