Query FRED (Federal Reserve Economic Data) API for 800,000+ economic time series from 100+ sources. Access GDP, unemployment, inflation, interest rates, exchange rates, housing, and regional data. Use for macroeconomic analysis, financial research, policy studies, economic forecasting, and academic research requiring U.S. and international economic indicators.

查询FRED（美联储经济数据）API，获取来自100多个来源的80多万条经济时间序列数据。访问国内生产总值、失业率、通货膨胀率、利率、汇率、房地产及区域数据，适用于宏观经济学分析、金融研究、政策研究、经济预测以及需要美国和国际经济指标的学术研究。