As recalled above, due to the Covid-19 health emergency, in the current weeks many hotels are not active.[1] The HAI index simply measures, at a certain date, the share of hotels posting availability of rooms for future check-in dates, over the total city sample. Different advance bookings are considered: 1 day, 14, days, 28 days, 56 days, 140 days. This index is calculated each Tuesday (starting retroactively from 2020, February 11th), and is published every Wednesday, starting from 2020, April 15 on this page.
The HAI is calculated on a 3-term exponential moving average and the details of the advance bookings (AB) and the acronyms of the derived curves are shown in the following table:
Curve acronym
Advance booking considered
AB=1_day
0,1,2
AB=14_days
13,14,15
AB=28_days
27,28
AB=56_days
56
AB=140_days
140
[1] Hotels that offer rooms at "abnormal" prices (above € 1000 or below € 19 per person per night) are considered "inactive".