|In September 2015,
a total of 1,952 exoplanets were known.
According to the "Habitable Exoplanets Catalog"
 there are 31 star systems with
planets in habitable zones. 21 were
superearth and only 10 were classified
as approximatly earth-great. Only in 4
systems could you classify planets as approximatly
If 31 systems of 1,952 systems have habitable planets, this corresponds to a share of 1.588 %, so: Fh2 = 0.015,88 = 31: 1,952.
NASA released on 9 May 2016, the latest data on the Kepler telescope.   In the meantime, 1,284 new exoplanets have been discovered.Thus, a total of 2,325 exoplanets are now known. There are probably rocky planets in 550 systems, like Earth. 9 planets are in a habitable zone.
Thus, the probability is Fh3 = 0.016,36 = 9:550 for habitable planets.
According to Wikipedia, as of October 1, 2017, a total of 3,671 exoplanets in 2,751 systems are known, including 616 systems with two to seven planets. 
According to the "Habitable Exoplanets Catalog"  of December 2017, 53 star systems with planets exist in habitable zones. 30 are super-earths, 22 are classified as approximately earth-great and a planet of the class subearth, thus planets which are smaller than the earth. Only in 5 of 13 selected systems, planets could be classified as approximately earth-like.
If of 2,751 known star systems with planets, 53 systems with habitable planets exist, then the probability is Fh4 = 0.019,265 = 53:2.751for habitable planets.
The data from 2015 to 2017 show the minimum and maximum probability of a planet in the habitable zone:
quite well with the value Fh1 = 0.016,588 =
10:603 from the Petigura investigation. The error is 4
results in a good agreement between the Petigura data and
the observations made in the meantime and the resulting
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