Unit 2 Economics - HDI question ? Confusion

I've learnt it as Real GDP per Capita ​

Hi

Short q

Was wondering whether the measure of income for HDI is GDP per capita or GNI per capita? My Edexcel book from 2011 says GDP per capita but my teacher says it's been changed to GNI recently. WTF is it actually? Tried to look on past mark schemes for clarification but not one I've found defines HDI.


Clarification would be much appreciated and I would be really grateful

Personally I think it's GNI but going against the book feels strange

Since 2010 the indicators have changed. GNI per capita is correct, although I've read the examiners report and they've said that candidates who say GDP per capita will be awarded the marks.