XML 33 R20.htm IDEA: XBRL DOCUMENT v3.23.1
Note 5 - Warrants (Tables)
12 Months Ended
Dec. 31, 2022
Notes Tables  
Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]
  Number of Shares Under Outstanding Warrants at December 31, 2022  Number of Shares Under Outstanding Warrants at December 31, 2021  Weighted Average Exercise Price at December 31, 2022  

Remaining Contractual Life at December 31, 2022 (Years)

 

Liability Classified Warrants (1)

                

Issued February 2017

     67,349  $    

Issued February 2018

  378,951   378,951   16.80   0.6 

Issued June 2018 (2)

  123,836   123,836   12.20   0.9 

Issued March 2019

  263,507   263,507   6.60   1.2 

Issued April 2019

  875,001   875,001   10.50   1.3 

Issued February 2020

  1,015,001   1,015,001   6.30   2.6 
   2,656,296   2,723,645  $9.49     

Equity Classified Warrants

                

Issued July 2017 - Consulting (3)

     25,001  $15.64    

Issued August 2019 - Consulting

     25,000   9.84    

Issued April 2020 - Consulting

  16,667   16,667   6.84   2.3 

Issued December 2020 - Consulting

  8,334   8,334   4.72   3.0 

Issued April 2021 - Consulting

  71,500   71,500   3.63   3.3 

Issued August 2021 - Consulting

  250,000   250,000   3.08   8.6 

Issued June 2022 - Consulting

  50,000      1.49   9.5 

Issued September 2022 - Consulting

  250,000      1.24   9.7 
   646,501   396,502  $2.42     

Balance outstanding

  3,302,797   3,120,147  $8.10     
Schedule of Warrants or Rights, Assumptions Used [Table Text Block]
  

Year Ended December 31,

 
  

2022

  

2021

 

Risk-free interest rate

  4.2% to 4.8%   0.1% to 1.1% 

Volatility

  63.1% to 76.3%   71.8% to 114.5% 

Expected life (years)

  0.1 to 2.6   0.1 to 3.6 

Dividend yield

  

—%

   

—%

 
Schedule of Warrant Activity [Table Text Block]
  Number of Shares Under Warrant  Range of Warrant Exercise Price per Share  Weighted Average Exercise Price  

Weighted Average Remaining Contractual Life (Years)

 

Outstanding at December 31, 2021

  2,723,645  

6.60 to 16.80

  $9.46   2.6 

Granted

    

6.30 to 6.30

  $    

Exercised

    

6.60 to 6.60

  $6.60    

Expired

  (67,349) 8.10 to 9.00  $8.42    

Outstanding at December 31, 2022

  2,656,296  6.30 to 16.80  $9.49   1.7 
                 

Vested and Exercisable at December 31, 2022

  2,656,296  6.30 to 16.80  $9.49   1.7