What is the most important financial indicators and analysis of interest to investors when the company evaluated.

1-  Current ratio

2-  Profit margin

3- Interest coverage ratio

4- Assets turnover

5- Leverage ratio

6- Cash cycle  

7- Total Liabilities to Total Assets

!. Profitability

2. Debts

3. Liquidity

4. Net Worth

5. Clients

6. Past performance

At the beginning the first indicator is IRR (Internal Rate of Return)

then to follow financial analysis

Profitability Ratios

Liquidity Ratios

Solvency Ratios

Debit Ratios

Variance Analysis

All that ratios and indicators have to calculate by making comparison with industry average and competitors indicators   

- No of Employees

- No. and type of Clients

- Business Net worth

- Market Capitalization

- Last3 Year Financial Performance

From my point of view, there is no one indicator as "the" most important

It's true that IRR is the most common to check, however, you have to take a look at a large number of ratios to have a real understanding of the project and its potentials. 

Thanks for invitation but, your question is not so clear for me. Do you mean economical evaluation of investments proposals?