The Mumbai jamboree was the biggest in India, but earlier events such as the "Vibrant Gujarat" launched by Modi when he led the state have only seen 13 percent of deals implemented, according to independent research.
Amitabh Kant, Secretary of India's Department of Industrial Policy and Promotion (DIPP), told reporters investment commitments had reached Rs. 15,20,000 crores ($222 billion).
The commitments fell some way short of the 25 trillion rupees announced at the three-day Vibrant Gujarat event a year ago.
Kant said he expected 80-85 percent of the pledges to convert into serious business, much of it from foreign investors. It can take 18 months to three years for a memorandum of understanding to yield a final investment, he added.
"This was the biggest multi-sectoral event ever done across Asia," he told a briefing, describing the event as a success.
Research commissioned by the free-market Friedrich Naumann and Cato institutes has found the rate of conversion of such pledges into real investments in India has typically been far lower - with no state exceeding 20 percent.
Among investments signed in the last seven days were a commitment by Oracle Corp for $400 million (roughly Rs. 2,747 crores) to set up nine business incubation centres.
Though some participants who spoke to Reuters lauded the event, several complained about a lack of foreign involvement.
"The response is overwhelming, but mostly from Indians. There are Indians everywhere. Usually in Germany, in events like these, stalls are thronged by foreigners," said Ingo Eibbeck, a representative of German manufacturer Schneider International.
© Thomson Reuters 2016
For the latest tech news and reviews, follow Gadgets 360 on X, Facebook, WhatsApp, Threads and Google News. For the latest videos on gadgets and tech, subscribe to our YouTube channel. If you want to know everything about top influencers, follow our in-house Who'sThat360 on Instagram and YouTube.