How do I explain Analysis of Companies Book Value Per Share (BVPS)

I have the numbers but I don't know how to explain the numbers. I'm trying to compare IBM and HP's BVPS here are my numbers for both

HP

Price/Book Value Ratio = Stock price per share/Shareholders' Equity per Share

2015 ($106,882B-$78,731B)/1,836B = 15.33 of book value (P/B ratio is $11.07/15.33 =.72)

2016 ($28,987B-$32,876B)/1,743B = -(2.23) of book value (P/B ratio is $13.63/-2.23 = -6.11)

2017 ($32,913B-$36,321B)/1,702B = -(2.00) of book value (P/B ratio is $20.89/-2.00 = -10.445)

2018 ($34,622B-$35,261B)/1,634B = -(.40) of book value (P/B ratio is $23.97/-.40 = -59.925)

2019 ($96,841B-$101,296B)/4,611B = -(.96) of book value (P/B ratio is $18.41/-.96 = -19.17) (As of Q3)

IBM

Price/Book Value Ratio = Stock price per share/Shareholders' Equity per Share

2015 ($110,495B-$96,071B)/983M = 14.67 of book value (P/B ratio is $120.66/14.67 = 8.22)

2016 ($117,470B-$99,078B)/959M = 19.17 of book value (P/B ratio is $151.05/19.17 = 7.87)

2017 ($125,356B-$107,631B)/937M = 18.92 of book value (P/B ratio is $145.03/18.92 = 7.66)

2018 ($123,382B-$106,453B)/916M =18.48 of book value (P/B ratio is $122.35/18.48 = 6.07)

2019 ($B-$2B)/M = 0 of book value (P/B ratio is $/ = 0) (As of Q2