Over the last four trading days, major banks displayed a bullish trend. A number of positive developments have boosted investor confidence in the industry. Clearance of stress test by all participating banks, improved global economic growth, expected lesser regulations and consistent rise in interest rates seem to be the driving factors. Moreover, expected bigger capital payouts by major banks, after the approval of their capital plans, added to the optimism.Following a rise in long-term bond yields on concerns over the Federal Reserve’s monetary strategies, mortgage rates climbed this week to hit 3.96%. In addition, the benchmark 10-year Treasury yield improved to 2.387%, marking the highest level in the last two months.Notably, mortgage applications improved slightly last week, per the latest data from the Mortgage Bankers Association. In addition, the refinance share of mortgage activity came in at 44.9% of all applications. However, homeowners seeking lower rates for refinancing are definitely big-time losers.Nevertheless, streamlining operations and acquisitions to enhance profitability have been witnessed over the last four trading days.(Read: Bank Stock Roundup for the week ending Jun 2, 2017)Important Developments of the Week1. The e-commerce business is fast growing with increasing number of consumers preferring to make payments using mobile phones and other electronic devices to cash transactions. Therefore, JPMorgan Chase & Co. JPM and Vantiv, Inc. VNTV, a credit card technology firm, have separately approached Worldpay Group Plc with preliminary takeover offers.Worldpay, UK’s largest payment-processing company, offers technology-led solutions to merchants and other businesses, which enable them to accept and settle payments made by their customers using mobile phones and other devices.As increasing number of people have started avoiding cash transactions, the payment processing industry has started gaining importance. This has made banks, credit card companies and other technology firms target such payment servicers in order to take advantage of the growing need for digital and card payments. (Read more: JPMorgan and Vantiv in Race for Worldpay Takeover)2. KeyCorp’s KEY banking subsidiary, KeyBank National Association, has successfully completed the acquisition of HelloWallet from Morningstar, Inc. Financial terms of the deal, which was announced in May, have not been disclosed yet. HelloWallet, a personal financial software product, provides financial assistance and guidance to its users by looking at their financial health and giving them a score based on the same.KeyBank has been using the HelloWallet software since 2015, which has helped hundreds of its clients improve their financial wellness score. So far, KeyBank has benefited from its relationship with HelloWallet and liked the high-tech software very much. With the completion of its acquisition, KeyBank is now in a better position to support its clients. (Read more: KeyCorp Closes HelloWallet Purchase from Morningstar)3. As part of its 2017 capital plan (approved by the Federal Reserve), The PNC Financial Services Group, Inc. PNC board of directors announced a 36% hike in the company’s quarterly common stock dividend. The revised quarterly dividend now comes in at 75 cents per share compared with the previous figure of 55 cents. This dividend will be paid on the next business day of Aug 5 to shareholders of record as of Jul 17.Price PerformanceHere is how the seven major stocks performed: CompanyLast Week6 monthsJPM2.7%9.7%BAC1.9%9.6%WFC0.3%2.3%C1.1%12.3%COF-0.6%-6.4%USB0.5%2.8%PNC0.9%6.8%In the last four trading sessions, JPMorgan and Bank of America Corp. BAC were the major gainers, with their shares increasing 2.7% and 1.9%, respectively. Furthermore, Citigroup Inc. C ascended 1.1%.Citigroup and JPMorgan were the best performers over the last six months, with their shares jumping 12.3% and 9.7%, respectively. Additionally, BofA’s shares increased 9.6%.What’s Next?The focus will solely be on earnings releases next week. Bank of the Ozarks, Inc. OZRK is scheduled to start off the season on Jul 12. Among Wall Street giants, JPMorgan, Citigroup, PNC Financial and Wells Fargo & Company WFC will report earnings on Jul 14.Will You Make a Fortune on the Shift to Electric Cars?Here's another stock idea to consider. Much like petroleum 150 years ago, lithium power may soon shake the world, creating millionaires and reshaping geo-politics. Soon electric vehicles (EVs) may be cheaper than gas guzzlers. Some are already reaching 265 miles on a single charge.With battery prices plummeting and charging stations set to multiply, one company stands out as the #1 stock to buy according to Zacks research.It's not the one you think.See This Ticker Free >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report J P Morgan Chase & Co (JPM): Free Stock Analysis Report PNC Financial Services Group, Inc. (The) (PNC): Free Stock Analysis Report KeyCorp (KEY): Free Stock Analysis Report Wells Fargo & Company (WFC): Free Stock Analysis Report Citigroup Inc. (C): Free Stock Analysis Report Bank of America Corporation (BAC): Free Stock Analysis Report Bank of the Ozarks (OZRK): Free Stock Analysis Report Vantiv, Inc. (VNTV): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research