most profitable inventions In the early 20th century, famous American economist elvin fisher developed the theory of economic gain. In its book "the nature of capital and yield", first, the concept of yield is analyzed in terms of the performance of earnings, and three different types of benefits are proposed: Diversification of securities, the establishment of a scientific and effective portfolio of securities; In the early hours of Wednesday, crude oil inventories were down (though gasoline inventories rose), boosting U.S. oil prices, according to zero hedge, a leading financial blog. But oil inventories in the EIA fell by five weeks, while gasoline inventories rose in six weeks and oil prices were volatile. In addition, us crude oil output was at a record high. Currently, us oil is trading at $57.56. The oil was trading at $63.95, up 0.25%. At this year's Shanghai international wine and spirits trade exhibition, we found more and more Brazilian exhibitors. It is believed that with the deepening of china-pakistan economic and trade relations, Brazilian wines can make a big difference in the Chinese market. Late last year, as Brazil's wine industry "leader" of the aurora winery has completed a total for the Chinese as much as 2.16 million barrels of wine export agreement, broke the single export record the wine industry in Brazil, which may be the trend of arguments. On Wednesday, on the first four shopping days of Christmas, upscale stores were discounting heavily, including most of the fashion retailers. H&M offers discounts of up to 60%, while Debenhams, Fraser, French connections, gaps, new faces and Dorothy Perkins offer discounts of up to 50%. It is worth mentioning that Surface Pro is by far the most popular with users of Surface equipment, Surface Pro 4 proportion is as high as 39.7%, Surface Pro 3 also is as high as 21.7%, while older equipment Surface Pro/Pro 2 still has 5.6% and 3.7% of the users. On the Surface Book, however, the average user accounts for just 0.4 per cent of the market, except for the 7.5 per cent share of the first generation, which may be due to a short listing. Commenting on the recent renovations, Ms Stephens said: “I am absolutely delighted with the work that has been carried out and Dortech’s customer service and professional installation has been second to none.