And we proved that again with an all-time ammonia production record of 10.4 million tons.
Our sales and logistics team rose to the challenge and set all-time sales and shipping records of over 20 million product tons.
This supports our projection of 90 million to 92 million planted corn acres in the US this year with upside potential.
We expect the urea tender volumes in India this year will be well above the five year average and close to the 10 million metric tons of last year.
For Brazil, we project 2021 imports of urea to be approximately 6.57 million metric tons, similar to last year.
For 2020, the company reported net earnings attributable to common stockholders of $317 million or $1.47 per diluted share.
EBITDA was $1.32 billion and adjusted EBITDA was $1.35 billion.
Net cash provided by operating activities was $1.2 billion and free cash flow was approximately $750 million.
As you can see on slide 9, we converted more than 55% of our adjusted EBITDA into free cash in 2020, which is the highest rate among our peers.
This will lower our gross debt to $3.75 billion.
We anticipate that our capital expenditures for 2021 will be in the range of $450 million.
Our annual cash interest expense will fall to $175 million with the repayment of the 2021 notes.
With our planned maintenance schedule and recent gas driven curtailments, we expect gross ammonia production to be around 9.5 million to 10 million tons.

Summary:
For 2020, the company reported net earnings attributable to common stockholders of $317 million or $1.47 per diluted share.
We anticipate that our capital expenditures for 2021 will be in the range of $450 million.