Hey ,
Possibly I am doing something that is conceptually wrong in python practice.
When I run a loop over fundamental_df and extract 'net_tangible_assets' and 'net_debt' and take the ratio of both , I get negative ratios as well.
for stock in fundamental_df:
ind_grp = fundamental_df[stock]['morningstar_industry_group_code']
assets = fundamental_df[stock]['net_tangible_assets']
debt = fundamental_df[stock]['net_debt']
ad_ratio = (assets)/float(debt)
That is because one of the numbers is actually negative.
From the fundamentals help page:
net_tangible_assets
Net assets in physical form. This is calculated using Stockholders'
Equity less Intangible Assets (including Goodwill).
So I assume net_tangible_assets may be negative when Intangible Assets (including Goodwill) is more than Stockholders' Equity.
e.g.
2014-03-03 PRINT -59700000.0,1157400000.0,-0.0515811301192
2014-03-03 PRINT -9000000.0,1189000000.0,-0.00756938603869
2014-03-03 PRINT -659000000.0,18303000000.0,-0.0360050264984
2014-03-03 PRINT -36110000.0,249338000.0,-0.144823492608
2014-03-03 PRINT -852000000.0,3912000000.0,-0.217791411043
2014-03-03 PRINT -177984000.0,1914601000.0,-0.0929614055357
2014-03-03 PRINT -2089049000.0,4047648000.0,-0.5161142965
2014-03-03 PRINT -1204400000.0,3189100000.0,-0.377661409175
2014-03-03 PRINT -56058000.0,930941000.0,-0.0602164906262
2014-03-03 PRINT -31407317.0,2978326.0,-10.5452918854
2014-03-03 PRINT -232000000.0,1919000000.0,-0.120896300156
2014-03-03 PRINT -902083000.0,1352395000.0,-0.667026275607
2014-03-03 PRINT -2983700000.0,9397000000.0,-0.317516228584
2014-03-03 PRINT -1881889000.0,1419498000.0,-1.32574262169
2014-03-04 PRINT -59700000.0,1157400000.0,-0.0515811301192
2014-03-04 PRINT -9000000.0,1189000000.0,-0.00756938603869
2014-03-04 PRINT -659000000.0,18303000000.0,-0.0360050264984
2014-03-04 PRINT -36110000.0,249338000.0,-0.144823492608
2014-03-04 PRINT -852000000.0,3912000000.0,-0.217791411043
2014-03-04 PRINT -177984000.0,1914601000.0,-0.0929614055357
2014-03-04 PRINT -2089049000.0,4047648000.0,-0.5161142965
2014-03-04 PRINT -1204400000.0,3189100000.0,-0.377661409175
2014-03-04 PRINT -56058000.0,930941000.0,-0.0602164906262
2014-03-04 PRINT -31407317.0,2978326.0,-10.5452918854
2014-03-04 PRINT -232000000.0,1919000000.0,-0.120896300156
2014-03-04 PRINT -902083000.0,1352395000.0,-0.667026275607 
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