Rockfort Express: திருச்சி அவனது கோட்டை, இரவில் சென்னை வரை வேட்டை, அவன் தான் மலைக்கோட்டை. - Vijay Baradwaj

This article explains it - /news/post/328731
“The Union Budget speech has, over the years, become a tool for the government to spread the goodies by way of announcements. While we get carried away by the announcements, the actual intent of the ministry will be known when you see the Pink Book.
For example, the Union Finance Minister might announce a project of Rs 2,000 crore, but by allotting just Rs 1 lakh for it in the Pink Book, he is signalling that the ministry isn’t too keen on the project. Sometimes it...
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also signals that a particular project can be kept on the backburner for a little while. For example:- “Against a cost of Rs.57 crore to extend platform numbers 10, 11, 12 and 13 at CST to handle 24 coach trains, the allotment in the Pink Book for 2015-16 was a mere Rs 1 lakh. It means the work can wait.”