  The purpose of this study is to propose a new index to measure and reflect
China's investment activity in time, and to analyze the changes of China's
investment activity in the past five years. This study first uses the NEZHA
model for semantic representation, and expand the indicator system based on
semantic similarity. Then we calculate China's investment activity index by
using the network search data. This study shows that China's investment
activity began to decline in 2019, rebounded for a period of time after the
outbreak of COVID-19 in 2020, and then continued to maintain a downward trend.
Private investment activity has declined significantly, while government
investment activity has increased. Among the provinces in Chinese Mainland, the
investment activity of economically developed provinces has decreased
significantly, while the investment activity of some economically less
developed provinces in the north and south is higher. After the outbreak of
COVID-19, the investment period became shorter. Our research will provide
timely investment information for the government, decision makers and managers,
as well as provide other researchers who also pay attention to investment with
a perspective other than investment in fixed asset.
