This article will provide a breakdown of commonly used acronyms, along with calculations used to formulate the metrics.

Digital Media Acronyms

• CTR = Click Thru Rate
• CPM = Cost Per Thousand
• CPC = Cost Per Click
• Cost = Budget or cost for that media
• CPA = Cost per Acquisition [action]
• ROAS = return on ad spend
• ADR = Average Daily Rate
• Conversion Rate = % of people who convert (book) compared to all users exposed to the ad
• Check Availability Rate = % of people who check availability
• Booking Engine Conversion Rate = % of people who convert (book) compared to all users exposed to the ad that entered the booking engine
• ALOS = average length of stay
• SOV = share of voice
• REVPAR = revenue per available room

Formulas

• Cost = Impressions x CPM/1000
• Impressions = Cost/CPM x 1000 or clicks/CTR [% /1000]
• Clicks = Cost/CPC or Impressions * CTR
• CPM = Cost/Impressions x 100 (conversion rate)
• CPC = Cost/Clicks
• CPA = Cost/Actions
• ROAS = Revenue /Spend
• ADR = Revenue / Number of nights
• Conversion Rate = Booking / Clicks
• Display Conversion Rate = Bookings / Impressions
• Check Availability Rate = Check Avails / Clicks
• Display Check Availability =  Check Avails / Impressions 
• Booking Engine (conversion) Rate = Bookings / Check Avails
• ALOS = Nights / Bookings
• AOV = Revenue / Bookings
• REVPAR = Rooms Revenue / Rooms Available
• REVPAR = Occupancy % x ADR

Examples

Total Cost = $16,000

Total Impressions = 1,000,000

Total Clicks = 13,000

CPM = $16

CPC = $16,000 / 13,000 = $1.23 CPC

CTR = 13,000 / 1,000,000 x 100 = 1.3 % CTR

CPM = $16,000 / 1.000.000 x 1,000 = $16 CPM

Clicks = 1,000,000 x 1.3% = 13,000 Clicks or $16,000 / $1.23

Impressions = $16,000 / $16 x 1000 = 1,000,000

Impressions or 13,000 / .013